Is telnet failover possible on SuSE?
Hello list, We have a login service that we would like to look at moving to a SuSE cluster of some sort. Our current platform (HP Tru64 UNIX 5.1B) allows for active telnet sessions to automatically failover to the other machine seamlessly to the client. As in you can type "ls -lR /sharedstorage" and while the data is streaming unplug the server you are connected to, there is a couple of second pause, and then it picks up mid stream. The actual computing power requirements are very small as the users telnet to the machine (must remain telnet for policy reasons), log into a menu, and then the menu triggers and rsh (again, must remain rsh) to a another server. Is what we want to accomplish realistic on SuSE, and if so, what packages should we be looking at? -Alain
Black, Alain <ablack@bloodsystems.org> wrote:
Our current platform (HP Tru64 UNIX 5.1B) allows for active telnet sessions to automatically failover to the other machine seamlessly to the client. As in you can type "ls -lR /sharedstorage" and while the data is streaming unplug the server you are connected to, there is a couple of second pause, and then it picks up mid stream.
Is what we want to accomplish realistic on SuSE, and if so, what
No. Telnet is a TCP based service, and _any_ TCP session will break if a failover occurs. What Tru64 does is provide a modified telnet daemon that keeps track of existing sessions on both machines. -- It is easier to be a "humanitarian" than to render your own country its proper due; it is easier to be a "patriot" than to make your community a better place to live in; it is easier to be a "civic leader" than to treat your own family with loving understanding; for the smaller the focus of attention, the harder the task. -- Sydney J. Harris
On Thu, May 05, 2005 at 03:11:39PM -0700, Black, Alain wrote:
Hello list,
We have a login service that we would like to look at moving to a SuSE cluster of some sort.
Our current platform (HP Tru64 UNIX 5.1B) allows for active telnet sessions to automatically failover to the other machine seamlessly to the client. As in you can type "ls -lR /sharedstorage" and while the data is streaming unplug the server you are connected to, there is a couple of second pause, and then it picks up mid stream.
openSSI could probbly do it (http://www.openssi.org), but it is not in any way supported by SUSE. At some point they were working on a SLES based build though.
The actual computing power requirements are very small as the users telnet to the machine (must remain telnet for policy reasons), log into a menu, and then the menu triggers and rsh (again, must remain rsh) to a another server.
Is what we want to accomplish realistic on SuSE, and if so, what packages should we be looking at?
If you want the ls to pick up seamlessly probably not without extensive changes like openssi. If all you want is some frontend one can rsh/telnet/ssh too that picks up a working a machine then then that would be probably possible with one of the cluster tools like heartbeat and a small frontend machine. That will just get you a working shell for each login though, no direct process failover. -Andi
participants (3)
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Andi Kleen -
Black, Alain -
Harald Milz