dhcp works, static ip addresses don't.
So, first off, I think SuSE (and Linux in general) has made great strides in the development of Linux. It's becoming as easy (perhaps, to some, easier) then Windoze to install. Still not as easy to use, but it'll get there.... Anyhow, one thing I can't seem to figure out is how to get a static ip address to work with a nameserver located at my ISP. Essentially, when I use a static IP address, i can't look up any address via their name, although I can reach them via the direct IP address. When I use DHCP to get the hosts IP address, but turn off it's ability to modify the /etc/resolv.conf file, then DNS seems to work. My /etc/resolv.conf reads as such: domain spiffy nameserver 207.155.183.72 nameserver 206.173.119.72 both with and without DHCP. But again, only when using DHCP do names seem to be found. When using a static IP address, they can't be. Can anyone think of a reason for this, or what I can look at to determine why this is happening? I'm a bit confused, and I'd prefer not to have one of my machines dynamically configured (it's my website address, which doesn't really work very well if the IP address keeps changing :)) Thnx, --jim -- -------- When I read about the evils of drinking, I gave up reading.
On Fri, Sep 21, 2001 at 11:12:48PM -0700, Jim Matzdorff wrote:
Anyhow, one thing I can't seem to figure out is how to get a static ip address to work with a nameserver located at my ISP.
Essentially, when I use a static IP address, i can't look up any address via their name, although I can reach them via the direct IP address.
When I use DHCP to get the hosts IP address, but turn off it's ability to modify the /etc/resolv.conf file, then DNS seems to work.
My /etc/resolv.conf reads as such:
domain spiffy nameserver 207.155.183.72 nameserver 206.173.119.72
both with and without DHCP. But again, only when using DHCP do names seem to be found. When using a static IP address, they can't be.
I am not sure I can answer this..but quite possibly if your ISP has allocated you a static IP address you may still need to use DHCP if you provider has so set it up (mine does with ADSL for example). Remember that DHCP can be configured to always give the same address to particular hosts. That really does not explain why your DNS lookup's fail ... -- Regards Cliff
** Reply to message from Cliff Sarginson
The idea of static IP's behind your gateway is explanied in the LDP
via http://www.wdm.com/LDP/HOWTO/Networking-Overview-HOWTO.html
and in RFC 1631 "The IP Network Address Translator"
RFC 2663 "IP Network Address Translator (NAT) Terminology and
Considerations."
/Dee
-----Original Message-----
From: Ed Harrison [mailto:ed.tman@verizon.net]
Sent: Saturday, September 22, 2001 2:45 PM
To: SuSE e-List
Subject: Re: [SLE] dhcp works, static ip addresses don't.
** Reply to message from Cliff Sarginson
The D in DHCP is for Dynamic which is not Static. Two approaches what could be considered "static" IP addresses... One is to max out the DHCP lease time in the device (router/server) that is "serving" out the DCHP addresses so that the address will never change once obtained by the requesting "host" (client) system. This is a 99.9% solution and it still possible to loose what one thought was a "fixed" IP address assignment given events that might flush the DHCP assignment table or a new network card since DHCP locks its IP address "lease" on the mac address of the network card. The other approach is to reserve addresses on the subnet within the subnet mask provided by your ISP and make real static IP addresse assignments. The next question might be public vs. private IP addresses and how you are going to make your "private" IP addressed systems visable on the "public" IP network, such as a web server, if you need to do so. Ed Harrison wrote:
** Reply to message from Cliff Sarginson
on Sat, 22 Sep 2001 09:39:13 +0200 # Remember # that DHCP can be configured to always give the same address to # particular hosts.
How does one get DHCP to give out the same address to a particular host?
I have a Linksys Router/Switch that has DHCP and I would love to be able to assign static IP addresses to each piece of equipment on my home network. I have 2 desktops, 1 laptop, 2 printers and 2 scanners.
Please tell that it is easy.
Ed Harrison, broadcasting on ----/ / _ ---/ / (_)__ __ ____ __ --/ /__/ / _ \/ // /\ \/ / -/____/_/_//_/\_,_/ /_/\_\ by SuSE(7.2), Kernel 2.4.9, X 4.1 or Windows98 (running in vmware 2.0.4 for fun) PolarBarMailer 1.20 with IBM JDK 1.3.0
Clint Tinsley wrote:
The D in DHCP is for Dynamic which is not Static. Two approaches what could be considered "static" IP addresses...
The dynamic part is not dynamic address selection, but dynamic configuration. It's purpose is to configure every machine on the network from one source instead of configuring each machine.
One is to max out the DHCP lease time in the device (router/server) that
The other approach is to reserve addresses on the subnet within the subnet mask provided by your ISP and make real static IP addresse
The ISC DHCP server will ALWAYS give the same address to the same MAC address if it is available (and it reserves it until all others are used up). I do know some providers are misusing DHCP to intentionally change IPs to keep people from web hosting on their net. There is also a fixed address argument to do just that, dynamically configure with a fixed address that never changes (because its address is not in the 'dynamic range'.
# that DHCP can be configured to always give the same address to # particular hosts.
How does one get DHCP to give out the same address to a particular host?
Check man dhcpd.conf, and look for fixed address. Basically, assign it in /etc/dhcpd.conf and make sure the address is not in the 'dynamic' range. -- Joe & Sesil Morris New Tribes Mission Email Address: Joe_Morris@ntm.org Web Address: www.mydestiny.net/~joe_morris "All I have seen teaches me to trust the Creator for all I have not seen." --Ralph Waldo Emerson
Joe & Sesil Morris (NTM) wrote:
Clint Tinsley wrote:
The D in DHCP is for Dynamic which is not Static. Two approaches what could be considered "static" IP addresses...
The dynamic part is not dynamic address selection, but dynamic configuration. It's purpose is to configure every machine on the network from one source instead of configuring each machine.
Well, sort of. Yes, it does push out to each machine the network configuration information of gateway, netmask and DNS which is all pretty "static" to the "connection" so that you don't have to manually configure this information. However, the real purpose of dynamic is to provide IP address assignment (as opposed to selection) from within a pool of available IP addresses which is where lease times comes into play. If lease times are short and according to what I have learned over the years is that at 50% of the lease time and if you had not "renewed" your lease, that IP address is released for assignment to another host. If you want the "Dynamic" IP address to be "permanent" subject to possible changes resulting from the DHCP table being flushed or changes in network card mac addresses, you "max" out the lease time in the router.
I do know some providers are misusing DHCP to intentionally change IPs to keep people from web hosting on their net.
On Dial-up's, the IP is actually static and assigned to a particular modem (I worked with a regional ISP for a time). On fixed connections, the point is correct that the ISP's do change the IP addresses to prevent users from setting up webservers, etc, unless you pay for such services. I believe the originator of this thread was requesting information on DHCP being provided by a router as opposed to a DHCP service being provided by a Linux box and it was in the router context that I provided this answer.
participants (6)
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Cliff Sarginson
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Clint Tinsley
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Ed Harrison
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Jim Matzdorff
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Joe & Sesil Morris (NTM)
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W.D.McKinney