On 2018-04-03 15:11, Frederic Crozat wrote:

Le mardi 03 avril 2018 à 15:03 +0200, Carlos E. R. a écrit :

...

Hi,

I just configured WiFi on this setup, and right now I have both eth0 and wlan active:

Minas-Anor:~ # ip addr 1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 link/ether 00:26:9e:95:62:d9 brd ff:ff:ff:ff:ff:ff inet 192.168.1.128/24 brd 192.168.1.255 scope global noprefixroute dynamic eth0 valid_lft 26835sec preferred_lft 26835sec inet6 fe80::2ec9:5fd7:5f20:24ed/64 scope link noprefixroute valid_lft forever preferred_lft forever 3: wlan0: mtu 1500 qdisc noqueue state UP group default qlen 1000 link/ether 0c:ee:e6:d7:bb:5f brd ff:ff:ff:ff:ff:ff inet 192.168.1.50/24 brd 192.168.1.255 scope global noprefixroute dynamic wlan0 valid_lft 43169sec preferred_lft 43169sec inet6 fe80::ecaa:bac3:4cfc:a41d/64 scope link noprefixroute valid_lft forever preferred_lft forever Minas-Anor:~ # Minas-Anor:~ # ip route default via 192.168.1.1 dev eth0 proto dhcp metric 100 default via 192.168.1.1 dev wlan0 proto dhcp metric 20600 192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.128 metric 100 192.168.1.0/24 dev wlan0 proto kernel scope link src 192.168.1.50 metric 600 Minas-Anor:~ #

I'm using Network Manager.

ping a local host works. Traceroute doesn't. ssh does.

Shouldn't one of the interfaces get automatically removed?

No, metrics is modified on the fly when wifi or ethernet goes up / down.

Interfaces should always be up.

Ok. But traceroute does not work. Can I make one to be automatically disabled when the other one connects? They are on the same network, it makes no sense to me. Not useful. -- Cheers/Saludos Carlos E. R. (testing openSUSE Leap 15.0, at Minas-Anor) -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 2018-04-03 15:41, James Knott wrote:

On 04/03/2018 09:26 AM, Carlos E. R. wrote:

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Interfaces should always be up.

Ok.

But traceroute does not work.

Can I make one to be automatically disabled when the other one connects? They are on the same network, it makes no sense to me. Not useful.

Why do you think traceroute doesn't work? Also, the interface with the lowest metric (Ethernet) will be used. Why is it necessary to shut down WiFi?

Minas-Anor:~ # traceroute 192.168.1.14 traceroute to 192.168.1.14 (192.168.1.14), 30 hops max, 60 byte packets 1 * * * 2 * * * 3 * * * 4 * * * 5 * * * 6 * * * 7 * * * 8 * * * 9 * * * 10 * * * 11 * * * 12 * * * 13 * * * 14 * * * 15 * * * 16 * * * 17 * * * 18 * * * 19 * * * 20 * * * 21 * * * 22 * * * 23 * * * 24 * * * 25 * * * 26 * * * 27 * * * 28 * * * 29 * * * 30 * * * Minas-Anor:~ # That's not working to me. I disable wifi: same result. I enable WiFi, remove eth cable: wifi goes up, ping fails for a minute: Minas-Anor:~ # ping 192.168.1.14 connect: Network is unreachable Minas-Anor:~ # ping 192.168.1.14 connect: Network is unreachable Minas-Anor:~ # ping 192.168.1.14 connect: Network is unreachable Minas-Anor:~ # A minute later it works. Traceroute fails the same. Well, traceroute failure is for some other reason, no idea what yet. In reverse direction, it does work: cer@Telcontar:~> traceroute 192.168.1.50 traceroute to 192.168.1.50 (192.168.1.50), 30 hops max, 60 byte packets 1 lap.windows.valinor (192.168.1.50) 2.449 ms !X 2.436 ms !X 2.694 ms !X cer@Telcontar:~> -- Cheers/Saludos Carlos E. R. (testing openSUSE Leap 15.0, at Minas-Anor) -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 2018-04-03 16:15, Per Jessen wrote:

Carlos E. R. wrote:

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In reverse direction, it does work:

cer@Telcontar:~> traceroute 192.168.1.50 traceroute to 192.168.1.50 (192.168.1.50), 30 hops max, 60 byte packets 1 lap.windows.valinor (192.168.1.50) 2.449 ms !X 2.436 ms !X 2.694ms !X

That !X means the icmp was rejected, I believe. Firewall?

Yes, the new firewall type. firewald? Yet it works. -- Cheers/Saludos Carlos E. R. (testing openSUSE Leap 15.0, at Minas-Anor) -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Dienstag, 3. April 2018 19:48:41 CEST Michal Suchánek wrote:

On Tue, 3 Apr 2018 09:41:50 -0400

James Knott wrote:

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On 04/03/2018 09:26 AM, Carlos E. R. wrote:

...

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Interfaces should always be up.

Ok.

But traceroute does not work.

Can I make one to be automatically disabled when the other one connects? They are on the same network, it makes no sense to me. Not useful.

Why do you think traceroute doesn't work? Also, the interface with the lowest metric (Ethernet) will be used. Why is it necessary to shut down WiFi?

To save power.

- Ethernet uses considerably more power than wireless - Idle wireless uses only a few mW - Connecting an ethernet cable is fine, but a power cable is not an option? Sorry, sounds like a strawman to me. But anyway, you /can/ disable it ... Regards, Stefan -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Tue, 3 Apr 2018 18:01:39 +0000 "Brüns, Stefan" wrote:

On Dienstag, 3. April 2018 19:48:41 CEST Michal Suchánek wrote:

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On Tue, 3 Apr 2018 09:41:50 -0400

James Knott wrote:

...

On 04/03/2018 09:26 AM, Carlos E. R. wrote:

...

...

Interfaces should always be up.

Ok.

But traceroute does not work.

Can I make one to be automatically disabled when the other one connects? They are on the same network, it makes no sense to me. Not useful.

Why do you think traceroute doesn't work? Also, the interface with the lowest metric (Ethernet) will be used. Why is it necessary to shut down WiFi?

To save power.

- Ethernet uses considerably more power than wireless

It is usually the other way around. Either way, having both powered requires more power than powering only one.

- Idle wireless uses only a few mW

When maintaining AP connection it is not really idle.

- Connecting an ethernet cable is fine, but a power cable is not an option?

It depends. I have usually more Ethernet cables than power adapters matching particular kind of notebook.

Sorry, sounds like a strawman to me. But anyway, you /can/ disable it ...

But the system does not do it for you and some people request it. It's not completely unreasonable to maintain only one connection to the same network. Thanks Michal -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Wed, 4 Apr 2018 15:59:18 +0000 "Brüns, Stefan" wrote:

On Mittwoch, 4. April 2018 13:49:09 CEST Michal Suchánek wrote:

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On Tue, 3 Apr 2018 18:01:39 +0000

"Brüns, Stefan" wrote:

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On Dienstag, 3. April 2018 19:48:41 CEST Michal Suchánek wrote:

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On Tue, 3 Apr 2018 09:41:50 -0400

James Knott wrote:

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On 04/03/2018 09:26 AM, Carlos E. R. wrote:

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> Interfaces should always be up.

Ok.

But traceroute does not work.

Can I make one to be automatically disabled when the other one connects? They are on the same network, it makes no sense to me. Not useful.

Why do you think traceroute doesn't work? Also, the interface with the lowest metric (Ethernet) will be used. Why is it necessary to shut down WiFi?

To save power.

- Ethernet uses considerably more power than wireless

It is usually the other way around. Either way, having both powered requires more power than powering only one.

Wireless power consumption: Intel, 2010: http://www.inf.ed.ac.uk/teaching/courses/cn/papers/halperin-hotpower10.pdf Cypress, 2017: http://www.cypress.com/file/298216/download

Ethernet power consumption: Intel, 2008: www.ieee802.org/3/az/public/jan08/hays_01_0108.pdf

Those are interesting papers. The Ethernet one seems to predate IEEE/802.3az, though.

-> Conclusion: If your equipment supports EEE/802.3az, ethernet comes close, if not ethernet is significantly worse.

Which is around for a while so I would expect most recent devices to support it. There were those "Green Ethernet" fake stickers on everything a few years back. Anyway, the fact that powering two network interfaces takes more than powering one stands. Thanks Michal -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 2018-04-03 15:11, H.Merijn Brand wrote:

On Tue, 3 Apr 2018 15:03:36 +0200, "Carlos E. R." wrote:

...

Hi,

I just configured WiFi on this setup, and right now I have both eth0 and wlan active:

Minas-Anor:~ # ip addr 1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 link/ether 00:26:9e:95:62:d9 brd ff:ff:ff:ff:ff:ff inet 192.168.1.128/24 brd 192.168.1.255 scope global noprefixroute dynamic eth0 valid_lft 26835sec preferred_lft 26835sec inet6 fe80::2ec9:5fd7:5f20:24ed/64 scope link noprefixroute valid_lft forever preferred_lft forever 3: wlan0: mtu 1500 qdisc noqueue state UP group default qlen 1000 link/ether 0c:ee:e6:d7:bb:5f brd ff:ff:ff:ff:ff:ff inet 192.168.1.50/24 brd 192.168.1.255 scope global noprefixroute dynamic wlan0 valid_lft 43169sec preferred_lft 43169sec inet6 fe80::ecaa:bac3:4cfc:a41d/64 scope link noprefixroute valid_lft forever preferred_lft forever Minas-Anor:~ # Minas-Anor:~ # ip route default via 192.168.1.1 dev eth0 proto dhcp metric 100 default via 192.168.1.1 dev wlan0 proto dhcp metric 20600 192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.128 metric 100 192.168.1.0/24 dev wlan0 proto kernel scope link src 192.168.1.50 metric 600 Minas-Anor:~ #

I'm using Network Manager.

ping a local host works. Traceroute doesn't. ssh does.

Shouldn't one of the interfaces get automatically removed?

I sincerely hope not! I quite often use both at the same time on different networks.

I can imagine that either is (automatically) disabled if both connect to the same network, which makes (some) sense

Which is the case, both are on the same network. -- Cheers/Saludos Carlos E. R. (testing openSUSE Leap 15.0, at Minas-Anor) -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 2018-04-03 15:39, James Knott wrote:

On 04/03/2018 09:24 AM, Carlos E. R. wrote:

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I can imagine that either is (automatically) disabled if both connect to the same network, which makes (some) sense

Which is the case, both are on the same network.

It is not the case. As I mentioned earlier, the interface metric is used to select the best interface. However, both are always up. Incidentally, this results in a benefit of Linux over Windows. On my notebook computer, I have different IP addresses for Ethernet & WiFi interfaces. When I connect with Ethernet and WiFi is connected, I can reach my WiFi address from my home network, as well as the Ethernet address. This means no matter how I'm connected I can connect to the notebook with the same IP address/host name. However Wireshark shows the traffic going through the Ethernet port, even when the WiFi address is used. This does not work with Windows. Then I have to specify a different address, depending on whether I have an Ethernet connection.

In this same laptop, when running 42.3, and using the same IP for both interfaces, I get "martians" and failures. I have to manually disable one (the wifi). I don't know the metrics in that case, I'll find out. When running Leap 15.0, different IP for each, different metrics, but same network - they connect to the same exact router, they are in the same segment - things work, except traceroute. -- Cheers/Saludos Carlos E. R. (testing openSUSE Leap 15.0, at Minas-Anor) -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Tue, 3 Apr 2018 10:36:20 -0400 James Knott wrote:

On 04/03/2018 09:44 AM, Carlos E. R. wrote:

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It is not the case. As I mentioned earlier, the interface metric is used to select the best interface. However, both are always up. Incidentally, this results in a benefit of Linux over Windows. On my notebook computer, I have different IP addresses for Ethernet & WiFi interfaces. When I connect with Ethernet and WiFi is connected, I can reach my WiFi address from my home network, as well as the Ethernet address. This means no matter how I'm connected I can connect to the notebook with the same IP address/host name. However Wireshark shows the traffic going through the Ethernet port, even when the WiFi address is used. This does not work with Windows. Then I have to specify a different address, depending on whether I have an Ethernet connection.

In this same laptop, when running 42.3, and using the same IP for both interfaces, I get "martians" and failures. I have to manually disable one (the wifi). I don't know the metrics in that case, I'll find out.

I never said use the same IP address for both interfaces. Only that Linux allows you to reach the WiFi address, even when connected via Ethernet.

And for a long time it allowed to reach the WiFi address even when it was on another network which is an information leak. It is none of your business what address the Linux box has on networks to which you are not connected. So much for Linux 'advantage'. Thanks Michal -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Tue, 3 Apr 2018 13:49:29 -0400 James Knott wrote:

On 04/03/2018 01:40 PM, Michal Such�nek wrote:

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I never said use the same IP address for both interfaces. Only that

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Linux allows you to reach the WiFi address, even when connected via Ethernet. And for a long time it allowed to reach the WiFi address even when it was on another network which is an information leak. It is none of your business what address the Linux box has on networks to which you are not connected. So much for Linux 'advantage'.

Linux is often used as a router and I have used it as one in the past (currently using pfSense on BSD). A router requires that function. Otherwise, it would be a useless router, if it couldn't connect to 2 networks at once.

If you're worried about it, turn off routing.

It is not about connecting to two networks. It is about connecting to two networks *separately* without leaking unneeded data between them. And that's exactly what a router or firewall is supposed to do. You completely miss the point. Thanks Michal -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Wed, 4 Apr 2018 09:00:01 -0400 James Knott wrote:

On 04/04/2018 07:51 AM, Michal Suchánek wrote:

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Linux is often used as a router and I have used it as one in the past

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(currently using pfSense on BSD). A router requires that function. Otherwise, it would be a useless router, if it couldn't connect to 2 networks at once.

If you're worried about it, turn off routing.

It is not about connecting to two networks. It is about connecting to two networks *separately* without leaking unneeded data between them. And that's exactly what a router or firewall is supposed to do. You completely miss the point.

Well, lets not forget that it's the user that connects to the 2 networks. If they didn't want to, then they wouldn't. Also, common practice these days is to use a firewall. Of course, for someone to take advantage of the connections to 2 networks they'd have to know about that.

What are you talking about? This is not about connecting to multiple networks. This is about not leaking information between different networks. net1 +--+ net2 | |PC| | +-----+--+----+ if1 if2 ip1 ip2 When I connect my PC to two networks I have not subscribed to connecting if2 to net1 and people in net1 should not see the ip2. Linux does show the ip2 the other devices connected to net1. This is broken and has been the default behavior in Linux for ages. These days with half dozen firewall types supported in the kernel you can probably craft a brittle firewalling rule to prevent this. However, this should not happen in the first place. As people these days still abuse this behaviour to access their WiFi IP over wired Ethernet it seems it has not changed - the bug is still there. Thanks Michal -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Wed, 4 Apr 2018 09:57:07 -0400 James Knott wrote:

On 04/04/2018 09:35 AM, Michal Suchánek wrote:

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Well, lets not forget that it's the user that connects to the 2

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networks. If they didn't want to, then they wouldn't. Also, common practice these days is to use a firewall. Of course, for someone to take advantage of the connections to 2 networks they'd have to know about that.

What are you talking about? This is not about connecting to multiple networks. This is about not leaking information between different networks.

net1 +--+ net2 | |PC| | +-----+--+----+ if1 if2 ip1 ip2

When I connect my PC to two networks I have not subscribed to connecting if2 to net1 and people in net1 should not see the ip2.

Linux does show the ip2 the other devices connected to net1.

This is broken and has been the default behavior in Linux for ages. These days with half dozen firewall types supported in the kernel you can probably craft a brittle firewalling rule to prevent this.

However, this should not happen in the first place. As people these days still abuse this behaviour to access their WiFi IP over wired Ethernet it seems it has not changed - the bug is still there.

As I mentioned, Linux can be used as a router, like Unix before it. Way back in the dark ages, many routers were simply mini computers running Unix. I was even able to configure OS/2 as a router. It's common behaviour. If you have a router, you're on at least 2 networks. A router would be useless otherwise. So, routing is not a bug. It's a function of most operating systems.

Now in the case on a computer, such as my notebook, if I'm connected on both interfaces, it's very likely to be the same network on both interfaces. How is that a problem? If I'm connected to 2 different networks, it's because I want to.

Assuming you're connected to 2 networks, what "leaks"? In order to access the other network, you would have to know that there's a computer acting as a router and then configure to use it as a router. You will not see things that might advertise the other network, such as broadcasts, as they are not passed by routers. So, what is it that's leaked?

The IP address and possibly other related information about the interface in the other network - even if you are not routing.

How does this compare to when you connect to the Internet via ISP? You're now connected to many networks and rely on a firewall to keep others out. Firewalls are now typically used on personal computers, even when connected to home networks. Also, the 2 interfaces are not bridged, as you seem to imply, so that's not how you'd have a leak.

And that's exactly the problem. Linux bridges those interfaces. Not the whole networks but the interfaces present on the box are visible to all connected networks even when you did not ask for it. Thanks Michal -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Wed, 4 Apr 2018 10:46:25 -0400 James Knott wrote:

On 04/04/2018 10:40 AM, Michal Suchánek wrote:

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The IP address and possibly other related information about the interface in the other network - even if you are not routing.

How does this happen, unless you're running a routing protocol such as OSPF? What mechanism is used to do this?

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...

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How does this compare to when you connect to the Internet via ISP? You're now connected to many networks and rely on a firewall to keep others out. Firewalls are now typically used on personal computers, even when connected to home networks. Also, the 2 interfaces are not bridged, as you seem to imply, so that's not how you'd have a leak. And that's exactly the problem. Linux bridges those interfaces. Not the whole networks but the interfaces present on the box are visible to all connected networks even when you did not ask for it.

It bridges interfaces when configured to do so. That's not the default. Interfaces are normally independent.

You may want to read up on how routers work.

Maybe you too ;-)

I'm a CCNA and have never heard of such a thing and I also frequently use Wireshark and haven't seen it either.

Read the other reply about weak host model. Supposedly this is not a bug but annoying design choice in Linux (different from eg. BSD). Thanks Michal -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Wed, Apr 04, 2018 at 03:35:03PM +0200, Michal Suchánek wrote:

What are you talking about? This is not about connecting to multiple networks. This is about not leaking information between different networks.

net1 +--+ net2 | |PC| | +-----+--+----+ if1 if2 ip1 ip2

When I connect my PC to two networks I have not subscribed to connecting if2 to net1 and people in net1 should not see the ip2.

Linux does show the ip2 the other devices connected to net1.

This is broken and has been the default behavior in Linux for ages. These days with half dozen firewall types supported in the kernel you can probably craft a brittle firewalling rule to prevent this.

However, this should not happen in the first place. As people these days still abuse this behaviour to access their WiFi IP over wired Ethernet it seems it has not changed - the bug is still there.

It's not a "bug", it's design decision ("weak host model" or "weak ES model" as described in RFC 1122). If you prefer strong host model, it's not that hard to emulate it e.g. with netfilter rules. Or perhaps using network namespaces might be considered more cool these days. Michal Kubeček -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 04/03/2018 03:54 PM, Carlos E. R. wrote:

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I never said use the same IP address for both interfaces. Only that Linux allows you to reach the WiFi address, even when connected via Ethernet.

But I do want both interfaces to have the same IP, and have only one active at a time. I want to do on another computer "ssh laptop" and be sure to reach it no matter if it is on WiFi or cable. I do not want to do "ssh laptop_eth" or "ssh laptop_wifi" depending.

That's the way it works here. No matter which address I use, when both connections are up, I can connect.

...

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When running Leap 15.0, different IP for each, different metrics, but same network - they connect to the same exact router, they are in the same segment - things work, except traceroute.

Make sure your firewall is turned off.

But I do want it on.

You can turn it off for testing.

Anyway, I disabled the firewall on the laptop and still traceroute fails.

It is the firewall (SuSEfirewall, Leap 42.3) at the destination that is the culprit.

The firewall at the target is the problem. It will block traceroute. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 04/03/2018 04:06 PM, Carlos E. R. wrote:

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That's the way it works here. No matter which address I use, when both connections are up, I can connect.

And how do you manage to do it automatically?

It just works with Linux, but not Windows.

On my "stable" partition, I have both eth0 and WiFi connections have the same IP and they collide, I get martians and failed connections. I have to disable one manually.

Again, you don't give them the same address. Give them different addresses. Then whether WiFi alone or both are connected, you can use the Wifi address.

I insist, I want to have both interfaces on the same address. The reason is to ssh from another machine and not having to think which interface it is using this time.

The only way I know is to manually disconnect one.

See above. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 2018-04-03 22:33, James Knott wrote:

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On 04/03/2018 04:06 PM, Carlos E. R. wrote:

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That's the way it works here. No matter which address I use, when both connections are up, I can connect.

And how do you manage to do it automatically?

It just works with Linux, but not Windows.

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On my "stable" partition, I have both eth0 and WiFi connections have the same IP and they collide, I get martians and failed connections. I have to disable one manually.

Again, you don't give them the same address. Give them different addresses. Then whether WiFi alone or both are connected, you can use the Wifi address.

But I insist I want to have the same address, and I do. I "simply" disable manually the WiFi when I notice.

I would like WiFi to detect the situation and disable itself automatically, on Linux. On Windows I do not care, but I think it disables itself automatically. I would have to confirm. "I think" ? Proof, Carlos, ICT is about 'true/false', '0/1', not about what one thinks or believes ( to remember ). Confirm this for yourself before

Op dinsdag 3 april 2018 23:48:05 CEST schreef Carlos E. R.: posting, it would make the discussion much easier. Another thing: having both or all network interfaces active is a feature, where you have set yourself to have a requirement that conflicts. I for one would never want two network devices on one machine having the same IP. And neither would I like to have the system deactivate one on activaition of the other one. To be honest, just the idea ... -- Gertjan Lettink a.k.a. Knurpht openSUSE Board Member openSUSE Forums Team -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 2018-04-04 00:46, Knurpht @ openSUSE wrote:

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On 2018-04-03 22:33, James Knott wrote:

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On 04/03/2018 04:06 PM, Carlos E. R. wrote:

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That's the way it works here. No matter which address I use, when both connections are up, I can connect.

And how do you manage to do it automatically?

It just works with Linux, but not Windows.

...

On my "stable" partition, I have both eth0 and WiFi connections have the same IP and they collide, I get martians and failed connections. I have to disable one manually.

Again, you don't give them the same address. Give them different addresses. Then whether WiFi alone or both are connected, you can use the Wifi address.

But I insist I want to have the same address, and I do. I "simply" disable manually the WiFi when I notice.

I would like WiFi to detect the situation and disable itself automatically, on Linux. On Windows I do not care, but I think it disables itself automatically. I would have to confirm. "I think" ? Proof, Carlos, ICT is about 'true/false', '0/1', not about what one thinks or believes ( to remember ). Confirm this for yourself before

Op dinsdag 3 april 2018 23:48:05 CEST schreef Carlos E. R.: posting, it would make the discussion much easier.

Common, man! I will of course confirm, but not today. I would have to reboot the machine and I don't intend to do it now. Please be patient.

Another thing: having both or all network interfaces active is a feature, where you have set yourself to have a requirement that conflicts. I for one would never want two network devices on one machine having the same IP. And neither would I like to have the system deactivate one on activaition of the other one. To be honest, just the idea ...

Well, you and I are different. I want both interfaces to have the same IP, and I want one to disable the other automatically, by some configuration that I can choose to activate, not for everybody. Do you understand now? -- Cheers/Saludos Carlos E. R. (testing openSUSE Leap 15.0, at Minas-Anor) -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Wed, 4 Apr 2018 14:03:34 +0200 "Carlos E. R." wrote:

On 04/04/2018 1:27, Carlos E. R. wrote:

...

On 2018-04-04 00:46, Knurpht @ openSUSE wrote:

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Op dinsdag 3 april 2018 23:48:05 CEST schreef Carlos E. R.:

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On 2018-04-03 22:33, James Knott wrote:

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On 04/03/2018 04:06 PM, Carlos E. R. wrote:

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> That's the way it works here.  No matter which address I use, > when both > connections are up, I can connect.

And how do you manage to do it automatically?

It just works with Linux, but not Windows.

...

On my "stable" partition, I have both eth0 and WiFi connections have the same IP and they collide, I get martians and failed connections. I have to disable one manually.

Again, you don't give them the same address.  Give them different addresses.  Then whether WiFi alone or both are connected, you can use the Wifi address.

But I insist I want to have the same address, and I do. I "simply" disable manually the WiFi when I notice.

I would like WiFi to detect the situation and disable itself automatically, on Linux. On Windows I do not care, but I think it disables itself automatically. I would have to confirm. "I think" ? Proof, Carlos, ICT is about 'true/false', '0/1', not about what one thinks or believes ( to remember ). Confirm this for yourself before posting, it would make the discussion much easier.

Common, man! I will of course confirm, but not today. I would have to reboot the machine and I don't intend to do it now. Please be patient.

Well, testing on Windows now.

I start with WiFi, then connect the cable: the network applet changes the icon to denote that ethernet and not wifi is in use now. However, the information on click seems to indicate that both are active. I log out and back in as another user, and now the network applet clearly indicates that the WiFi is not active. The machine lamp indicates that WiFi is powered.

I try again. Disconnect cable, WiFi icon appears on applet. I connect the cable back. The command "ipconfig" on terminal instantly shows that the WiFi IP has disappeared. Icon shows "cable". And detailed information shows that only ethernet is connected.

So it is confirmed: on this triple boot laptop, Windows 10 automatically disconnects the WiFi on ethernet cable connect. Different IP.

Which means it breaks your connections. That's the annoying part of this "feature" on Windows. Now I remember why it was broken there. You need same IP to do this. Thanks Michal -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 04/04/2018 08:30 AM, Carlos E. R. wrote:

In fact, I try to set up the same IP on Windows for both interfaces, and it fails: the eth does not accept 192.168.1.50 and goes instead to 169.254.4.71, and WiFi reactivates.

People usually use DHCP these days, so you'd never see the same address assigned to the 2 interfaces. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 04/04/2018 09:23 AM, Michael Ströder wrote:

James Knott wrote:

...

People usually use DHCP these days, so you'd never see the same address assigned to the 2 interfaces. It depends on your DHCP setup. ;-)

Ciao, Michael.

Are you aware of a DHCP server that will allow the same IP address for 2 different MACs on the same network at the same time? Normally, a MAC address "owns" the IP address for the duration of the lease. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 04/04/2018 09:34 AM, Michael Ströder wrote:

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Are you aware of a DHCP server that will allow the same IP address for 2

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different MACs on the same network at the same time? Normally, a MAC address "owns" the IP address for the duration of the lease. Yes, ISC dhcpd if you assign IP addresses by host declaration instead of letting it pick an IP address from a pool. I'm doing this at home but I know the side effects and act accordingly.

I do that too, but my DHCP server (pfSense) won't allow duplicate IP addresses. In fact, I accidentally ran into that yesterday, when I was trying to configure an address for my new tablet. ;) On my home network, I use static configuration for my main desktop, router and access point, but use DHCP with assigned addresses for everything else. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 04/04/2018 03:38 PM, Stefan Seyfried wrote:

Am 04.04.2018 um 15:29 schrieb James Knott:

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On 04/04/2018 09:23 AM, Michael Ströder wrote:

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James Knott wrote:

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People usually use DHCP these days, so you'd never see the same address assigned to the 2 interfaces. It depends on your DHCP setup. ;-)

Ciao, Michael.

Are you aware of a DHCP server that will allow the same IP address for 2 different MACs on the same network at the same time? Normally, a MAC address "owns" the IP address for the duration of the lease. dnsmasq:

seife@server:~> grep -v ^# /etc/dnsmasq.d/dhcp-hosts |grep ,.*, dhcp-host=00:26:2D:F4:38:84,00:21:6A:AD:D7:6C,susi dhcp-host=00:1f:16:11:d6:24,00:16:ea:e5:1a:26,x200-m dhcp-host=00:26:2d:f6:eb:fd,50:63:13:c1:75:00,x200-3 dhcp-host=00:22:68:0d:36:39,00:22:fa:cd:1e:3e,mixi dhcp-host=8c:70:5a:30:f2:d0,42:e5:21:69:6b:0f,00:21:cc:69:db:f2,strolchi dhcp-host=a0:88:b4:a3:85:68,00:21:cc:64:e5:33,bob dhcp-host=net:inst-32,00:0b:97:a0:cd:fc,00:12:f0:3e:96:e4,toughbook dhcp-host=net:inst-32,00:08:02:D5:98:6E,00:0E:35:F2:C9:EC,nc6000 [... many more... ]

What is it you're showing there? all I see is a bunch of MAC addresses, 2 per line, followed by what I assume are names. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

Citeren James Knott :

On 04/04/2018 08:30 AM, Carlos E. R. wrote:

...

In fact, I try to set up the same IP on Windows for both interfaces, and it fails: the eth does not accept 192.168.1.50 and goes instead to 169.254.4.71, and WiFi reactivates.

People usually use DHCP these days, so you'd never see the same address assigned to the 2 interfaces.

With DHCPv4 that may be the case, but DHCPv6 will usually assign by DUID (https://tools.ietf.org/html/rfc3315#section-9). Only fairly recently it has become feasible to use MAC addresses in DHCPv6 (https://tools.ietf.org/html/rfc6939). As long as I make sure WiFi and (wired) ethernet are not connected at the same time, the address they receive from my DHCPv6 server will be the same. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

James Knott wrote:

What happens if you have both interfaces active on the same network?

It still works for me and routing table has two different entries with different metric. I manually avoid that though just because it does not feel right and might confuse bad switches. Ciao, Michael.

On 04/04/2018 10:18 AM, Michael Ströder wrote:

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It still works for me and routing table has two different entries with

...

different metric. I don't run a LAN-accessible server on my laptop though.

Actually, you probably do. Can you connect to the laptop via ssh? If so, you have a server running. File sharing? Server again. Etc. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

Citeren James Knott :

On 04/04/2018 09:57 AM, Arjen de Korte wrote:

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Citeren James Knott :

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On 04/04/2018 08:30 AM, Carlos E. R. wrote:

...

In fact, I try to set up the same IP on Windows for both interfaces, and it fails: the eth does not accept 192.168.1.50 and goes instead to 169.254.4.71, and WiFi reactivates.

People usually use DHCP these days, so you'd never see the same address assigned to the 2 interfaces.

With DHCPv4 that may be the case, but DHCPv6 will usually assign by DUID (https://tools.ietf.org/html/rfc3315#section-9). Only fairly recently it has become feasible to use MAC addresses in DHCPv6 (https://tools.ietf.org/html/rfc6939).

As long as I make sure WiFi and (wired) ethernet are not connected at the same time, the address they receive from my DHCPv6 server will be the same.

What happens if you have both interfaces active on the same network?

That is where the Duplicate Address Detection (DAD) kicks in. The DHCPv6 server will offer the same address on both interfaces, but the client will reject one when it sees it is already in use. In which case it depends on the server configuration if another address if offered or not. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

Citeren James Knott :

On 04/04/2018 10:32 AM, Arjen de Korte wrote:

...

...

What happens if you have both interfaces active on the same network?

That is where the Duplicate Address Detection (DAD) kicks in. The DHCPv6 server will offer the same address on both interfaces, but the client will reject one when it sees it is already in use. In which case it depends on the server configuration if another address if offered or not.

I'm aware of DAD. But what happens when a DHCPv6 address is assigned to that DUID from 2 interfaces and one of them rejects it? I'm not running DHCPv6 on my LAN, so I can't check.

The client can use the address on the interface it configured with the assigned IPv6 address, wether or not the other interface receives an alternative address depends on the server configuration. Usually DHCPv6 is used for administrative reasons (keep track of who is doing what) and in that case it makes sense to not allow different addresses to be used. In which case it also makes sense to allow only one interface to be active at the same time (this reduces the burden of logging, since clients will always use the same IPv6 address, no matter how they connect). The lack of DHCPv6 support in Android limits the use to non-Android devices though, in which case it is not uncommon to block IPv6 entirely for that class of devices. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

Am 04.04.2018 um 15:03 schrieb James Knott:

People usually use DHCP these days, so you'd never see the same address assigned to the 2 interfaces.

I'm assigning the same address to wired and wireless via DHCP. Works very well with NetworkManager. qed ;-) -- Stefan Seyfried "For a successful technology, reality must take precedence over public relations, for nature cannot be fooled." -- Richard Feynman -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 2018-04-04 15:22, Michael Ströder wrote:

Carlos E. R. wrote:

...

On the Linux side I configured for the same IP, but on Windows I have not bothered because I use it rarely (and after all, I can not ssh-in to Windows). It might be a problem for Samba, though: I have to open ports on the Linux firewall for two different IPs for the same machine.

I wonder why you argue with the Windows behaviour if you don't have the very same requirements with this OS.

No, but the question arose about how Windows behaved in this situation.

BTW: I think what you want is best achieved by connecting your (IP-less) eth0 and wlan0 to a bridge interface and assign the IP to that.

Sorry, I don't understand. What I do, and works, is having the same IP on both eth0 and wlan0 interfaces. I "only" have to remember to disable wlan when I insert the cable. Now, Michal Kubecek has posted a suggestion that I want to try, using STARTMODE='ifplugd' and adjusting priorities. -- Cheers/Saludos Carlos E. R. (testing openSUSE Leap 15.0, at Minas-Anor) -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 04/04/2018 09:59 AM, Bengt Gördén wrote:

...

...

...

...

BTW: I think what you want is best achieved by connecting your (IP-less) eth0 and wlan0 to a bridge interface and assign the IP to that.

Sorry, I don't understand. You create a software bridge between eth0 and wlan0 and that the bridge has it's own IP configuration.

Another way might be to manually assign the MAC to both interfaces. That way, the same IP will be obtained, no matter which interface is used. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Wed, Apr 04, 2018 at 04:14:18PM +0200, Michael Ströder wrote:

James Knott wrote:

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On 04/04/2018 09:59 AM, Bengt Gördén wrote:

...

...

...

...

> BTW: I think what you want is best achieved by connecting your (IP-less) > eth0 and wlan0 to a bridge interface and assign the IP to that.

Sorry, I don't understand. You create a software bridge between eth0 and wlan0 and that the bridge has it's own IP configuration.

Another way might be to manually assign the MAC to both interfaces. That way, the same IP will be obtained, no matter which interface is used.

IMO the bridge is the most clean solution for having the same IP address for cable and wireless access.

As long as you are sure the switch(es) you are connecting to has (have) working STP. :-) Personally, I would rather suggest bond/team in active-backup mode (you can even set preferred slave to ethernet one). Also, IIRC most wlan devices can only be bridged when in "AP mode". Michal Kubeček -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

Am 04.04.2018 um 15:59 schrieb Bengt Gördén:

Like so: ip link add name br0 type bridge ip link set dev br0 up ip link set dev wlan0 master br0

Did you actually try this? Last time I tried, WLAN could not be bridged. -- Stefan Seyfried "For a successful technology, reality must take precedence over public relations, for nature cannot be fooled." -- Richard Feynman -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Apr 04 2018, Stefan Seyfried wrote:

Am 04.04.2018 um 15:59 schrieb Bengt Gördén:

...

Like so: ip link add name br0 type bridge ip link set dev br0 up ip link set dev wlan0 master br0

Did you actually try this? Last time I tried, WLAN could not be bridged.

Most home routers should be able to do it. Andreas. -- Andreas Schwab, SUSE Labs, schwab@suse.de GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7 "And now for something completely different." -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 2018-04-03 16:54, Michal Kubecek wrote:

On Tue, Apr 03, 2018 at 03:44:46PM +0200, Carlos E. R. wrote:

...

In this same laptop, when running 42.3, and using the same IP for both interfaces, I get "martians" and failures. I have to manually disable one (the wifi). I don't know the metrics in that case, I'll find out.

Using the same address for both would require a bit more work. And in general, don't forget to disable RP filter which is unfortunately still on by default.

I would prefer to configure on my system to disable WiFi automatically when I connect the cable. Not as a general thing, but as something to do on my system. A choice :-) -- Cheers/Saludos Carlos E. R. (testing openSUSE Leap 15.0, at Minas-Anor) -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

Michal Kubecek wrote:

On Tuesday, 3 April 2018 22:01 Carlos E. R. wrote:

...

On 2018-04-03 16:54, Michal Kubecek wrote:

...

On Tue, Apr 03, 2018 at 03:44:46PM +0200, Carlos E. R. wrote:

...

In this same laptop, when running 42.3, and using the same IP for both interfaces, I get "martians" and failures. I have to manually disable one (the wifi). I don't know the metrics in that case, I'll find out.> Using the same address for both would require a bit more work. And in general, don't forget to disable RP filter which is unfortunately still on by default.

I would prefer to configure on my system to disable WiFi automatically when I connect the cable. Not as a general thing, but as something to do on my system. A choice :-)

You might try to set STARTMODE='ifplugd' for both and give ethernet higher IFPLUGD_PRIORITY. I haven't tried myself but the descriptions in ifcfg.template mentions this particular case.

Another option would be if wicked allowed to run custom scripts on link up/down events - but I have no idea if wicked provides such feature.

I'm pretty certain scripts from /etc/sysconfig/network/if-{up,down}.d are also run by wicked. -- Per Jessen, Zürich (9.0°C) http://www.hostsuisse.com/ - dedicated server rental in Switzerland. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 2018-04-04 07:33, Michal Kubecek wrote:

On Tuesday, 3 April 2018 22:01 Carlos E. R. wrote:

...

On 2018-04-03 16:54, Michal Kubecek wrote:

...

On Tue, Apr 03, 2018 at 03:44:46PM +0200, Carlos E. R. wrote:

...

In this same laptop, when running 42.3, and using the same IP for both interfaces, I get "martians" and failures. I have to manually disable one (the wifi). I don't know the metrics in that case, I'll find out.> Using the same address for both would require a bit more work. And in general, don't forget to disable RP filter which is unfortunately still on by default.

I would prefer to configure on my system to disable WiFi automatically when I connect the cable. Not as a general thing, but as something to do on my system. A choice :-)

You might try to set STARTMODE='ifplugd' for both and give ethernet higher IFPLUGD_PRIORITY. I haven't tried myself but the descriptions in ifcfg.template mentions this particular case.

Is this on Network Manager? I don't see ifcg.template in my system. What I see on the desktop applet configuration is something called "connection priority for auto activation". Eth has -999 and wlan has 0 -- Cheers/Saludos Carlos E. R. (testing openSUSE Leap 15.0, at Minas-Anor) -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 2018-04-04 21:11, Michal Kubecek wrote:

On Wed, Apr 04, 2018 at 08:42:22PM +0200, Carlos E. R. wrote:

...

On 2018-04-04 07:33, Michal Kubecek wrote:

...

You might try to set STARTMODE='ifplugd' for both and give ethernet higher IFPLUGD_PRIORITY. I haven't tried myself but the descriptions in ifcfg.template mentions this particular case.

Is this on Network Manager?

No, I'm not using NetworkManager so you would need someone else to help you with it.

...

I don't see ifcg.template in my system.

Should be in /etc/sysconfig/network/ifcfg.template

Ah, yes, I see it now. "mlocate" did not find it.

It's a template for ifcfg-* files which also serves as a documentation of parameters that can be used in them.

Ah, pity. Then it doesn't apply to me, the laptop uses network manager. WiFi with changing locations is easier with NM. -- Cheers/Saludos Carlos E. R. (testing openSUSE Leap 15.0, at Minas-Anor) -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 04/03/2018 09:11 AM, H.Merijn Brand wrote:

I can imagine that either is (automatically) disabled if both connect to the same network, which makes (some) sense

No it doesn't. See my previous note about metric. The metric refers to the "cost" of the connection. Ethernet has a lower metric or cost, so is used in preference to WiFi. This is basic router operation. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 2018-04-03 15:31, James Knott wrote:

On 04/03/2018 09:03 AM, Carlos E. R. wrote:

...

Shouldn't one of the interfaces get automatically removed?

Why should it? What if the 2 connections are for different networks? That's allowed. What you will see happens, if on the same network, is Ethernet is preferred. This is determined by something called "metric". If you run the route command, you'll see a metric for each interface. The interface with the lowest metric is the one that's used. On my notebook computer, WiFi has a metric of 600, but Ethernet is 100, so Ethernet is used.

But it is the same network. route: command not found. Yes, I can install it, I know. Just curious that it wasn't by default. "ip route" shows that the metrics are different (100 and 600). Ok, if this is not wrong, why doesn't traceroute work? -- Cheers/Saludos Carlos E. R. (testing openSUSE Leap 15.0, at Minas-Anor) -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 04/03/2018 09:57 AM, Jan Engelhardt wrote:

...

Ok, if this is not wrong, why doesn't traceroute work? Because packets go out one interface and come back the other, which then trips up rp_filter? (Gotta wonder if rp_filter is still a thing..)

More likely a firewall blocking it. I have to turn off the firewall, on the target computer, to use traceroute. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 04/03/2018 04:12 PM, Carlos E. R. wrote:

Yes, that is the case.

Now, I wonder what to open on the destination firewall. It responds to pings, so traceroute must be using some other thing. I am reading the man now and I can't see a paragraph that says what exact port they use by default. Only that I can choose one.

It uses UDP. According to Wireshark, it starts at port 33434 and increments with each packet. I don't know how high it goes. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

Carlos E. R. wrote:

On 2018-04-03 22:37, James Knott wrote:

...

On 04/03/2018 04:12 PM, Carlos E. R. wrote:

...

Yes, that is the case.

Now, I wonder what to open on the destination firewall. It responds to pings, so traceroute must be using some other thing. I am reading the man now and I can't see a paragraph that says what exact port they use by default. Only that I can choose one.

It uses UDP. According to Wireshark, it starts at port 33434 and increments with each packet. I don't know how high it goes.

Thus it is impossible to open the firewall to it.

You don't.

From each router on the way to the destination, traceroute will receive an icmp-time-exceeded. From the target host, it will likely receive a icmp-port-unreachable.

-- Per Jessen, Zürich (7.7°C) http://www.dns24.ch/ - free dynamic DNS, made in Switzerland. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Wednesday, 4 April 2018 11:02 Carlos E. R. wrote:

On 2018-04-04 07:33, Per Jessen wrote:

...

...

From each router on the way to the destination, traceroute will receive>> an icmp-time-exceeded. From the target host, it will likely receive a icmp-port-unreachable.

Well, traceroute to the 15.0 laptop with firewald works just fine :-)

Well, it should depend on what your netfilter configuration looks like rather than if you are using firewalld or not. :-) Michal Kubeček -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Tue, Apr 03, 2018 at 03:57:07PM +0200, Jan Engelhardt wrote:

Because packets go out one interface and come back the other, which then trips up rp_filter? (Gotta wonder if rp_filter is still a thing..)

Three years ago when the question (of rp_filter being enabled by default) was discussed in bugzilla (the bug is not public, unfortunately), I tried to write down reasons why I thing it should be disabled by default. No chance, the idea was shut down with "rp_filter is the most basic spoof protection and we have it turned on by default since forever". :-( Michal Kubeček -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On Tuesday 2018-04-03 19:36, Michal Kubecek wrote:

On Tue, Apr 03, 2018 at 03:57:07PM +0200, Jan Engelhardt wrote:

...

Because packets go out one interface and come back the other, which then trips up rp_filter? (Gotta wonder if rp_filter is still a thing..)

Three years ago when the question (of rp_filter being enabled by default) was discussed in bugzilla

I was trying to hint at xt_rpfilter superseding the rp_filter sysctl knob; and I had not verified whether the sysctl tunable is still having an effect or just exists for compatibilty without function. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

Carlos E. R. wrote:

On 2018-04-03 15:31, James Knott wrote:

...

On 04/03/2018 09:03 AM, Carlos E. R. wrote:

...

Shouldn't one of the interfaces get automatically removed?

Why should it? What if the 2 connections are for different networks? That's allowed. What you will see happens, if on the same network, is Ethernet is preferred. This is determined by something called "metric". If you run the route command, you'll see a metric for each interface. The interface with the lowest metric is the one that's used. On my notebook computer, WiFi has a metric of 600, but Ethernet is 100, so Ethernet is used.

But it is the same network.

route: command not found. Yes, I can install it, I know. Just curious that it wasn't by default.

It's part of net-tools-deprecated, along with e.g. netstat. -- Per Jessen, Zürich (18.7°C) http://www.hostsuisse.com/ - dedicated server rental in Switzerland. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

James Knott wrote:

On 04/03/2018 10:07 AM, Per Jessen wrote:

...

It's part of net-tools-deprecated, along with e.g. netstat.

It's still useful.

Oh I agree. I don't use 'route' much, I default to "ip route" instead, but "netstat" is hardwired into my fingers. I'm trying to get used to "ss" instead. -- Per Jessen, Zürich (20.1°C) http://www.hostsuisse.com/ - dedicated server rental in Switzerland. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org

On 04/03/2018 11:05 AM, Michal Kubecek wrote:

On Tue, Apr 03, 2018 at 10:41:33AM -0400, James Knott wrote:

...

On 04/03/2018 10:07 AM, Per Jessen wrote:

...

It's part of net-tools-deprecated, along with e.g. netstat. It's still useful. Can you name one thing route can do that ip can't?

Michal Kube�ek

It's not just route. It's the whole net-utils package. I often use ifconfig, for example. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org