Re: [Linux-HA] How to set this up correctly...?
Howard Yuan wrote: > Okay...I got a working heartbeat setup...but...now I'm curious and > can't figure a way around this. Wondering if you guys have any idea. > > Currently, I have two SLES running DRBD and Heartbeat. Here are the > configs: > > Server A LAN 1: 192.168.15.30/255.255.255.0 LAN 2: > 10.0.0.2/255.255.255.0 > > Server B LAN 1: 192.168.15.31/255.255.255.0 LAN 2: > 10.0.0.4/255.255.255.0 > > LAN 1's is connected to the main network switch. LAN 2's are > connected to each other via a crossover cable. Heartbeat is serving > up MySQL and a floating IP address of 10.0.0.5/255.255.255.0. > > The question I'm having is...if the crossover cable breaks for any > reason...heartbeat never fails over (as the servers are technically > still alive), but the service is no longer accessible (as they're > trying to access it via 10.0.0.5). > > What is the best way to get around this problem? I want to make it > where the service is/will still be available whenever ONE of the > connection is broken..as the fail over doesn't occur until both > connections die. Any ideas? Why does the service die when the crossover breaks? I need more configuration information to give a detailed answer. But, the short answer is "run an R2 configuration with pingd properly configured for your problem" -- Alan Robertson <[EMAIL PROTECTED]> "Openness is the foundation and preservative of friendship... Let me claim from you at all times your undisguised opinions." - William Wilberforce ___ Linux-HA mailing list Linux-HA@lists.linux-ha.org http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
Re: [Linux-HA] How to set this up correctly...?
"Why does the service die when the crossover breaks?" Because I was planning on telling the services to look for MySQL on 10.0.0.5 (the floating IP) and if the crossover link breaks, the systems don't know how to get to 10.0.0.5 as they're looking to find it via the crossover link (LAN 2). "I need more configuration information to give a detailed answer." Hum...what information would you need to understand it better? I can try to draw an ASCII picture of the network diagram if you need me to. "But, the short answer is 'run an R2 configuration with pingd properly configured for your problem'" I looked at this for awhile and I can't figure out what you mean by "R2." Also, on my heartbeat configuration right now, i'm using "crm no" to use ipfail, as I found on the mailing list that someone said that ipfail doesn't work with crm. Does CRM include a replacement for ipfail that works better? Thank you for your response, Alan. >>> On 3/27/2007 at 5:09 AM, Alan Robertson <[EMAIL PROTECTED]> wrote: Howard Yuan wrote: > Okay...I got a working heartbeat setup...but...now I'm curious and > can't figure a way around this. Wondering if you guys have any idea. > > Currently, I have two SLES running DRBD and Heartbeat. Here are the > configs: > > Server A LAN 1: 192.168.15.30/255.255.255.0 LAN 2: > 10.0.0.2/255.255.255.0 > > Server B LAN 1: 192.168.15.31/255.255.255.0 LAN 2: > 10.0.0.4/255.255.255.0 > > LAN 1's is connected to the main network switch. LAN 2's are > connected to each other via a crossover cable. Heartbeat is serving > up MySQL and a floating IP address of 10.0.0.5/255.255.255.0. > > The question I'm having is...if the crossover cable breaks for any > reason...heartbeat never fails over (as the servers are technically > still alive), but the service is no longer accessible (as they're > trying to access it via 10.0.0.5). > > What is the best way to get around this problem? I want to make it > where the service is/will still be available whenever ONE of the > connection is broken..as the fail over doesn't occur until both > connections die. Any ideas? Why does the service die when the crossover breaks? I need more configuration information to give a detailed answer. But, the short answer is "run an R2 configuration with pingd properly configured for your problem" -- Alan Robertson <[EMAIL PROTECTED]> "Openness is the foundation and preservative of friendship... Let me claim from you at all times your undisguised opinions." - William Wilberforce ___ Linux-HA mailing list Linux-HA@lists.linux-ha.org http://lists.linux ( http://lists.linux/ )-ha.org/mailman/listinfo/linux-ha See also: http://linux ( http://linux/ )-ha.org/ReportingProblems -- Howard Yuan I.T. Department Valence Technology, Inc. http://www.valence.com/ ___ Linux-HA mailing list Linux-HA@lists.linux-ha.org http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
Re: [Linux-HA] How to set this up correctly...?
Howard Yuan wrote: > "Why does the service die when the crossover breaks?" Because I was > planning on telling the services to look for MySQL on 10.0.0.5 (the > floating IP) and if the crossover link breaks, the systems don't know > how to get to 10.0.0.5 as they're looking to find it via the > crossover link (LAN 2). OK. I understand that. So, mysql needs connectivity via the crossover cable. > "I need more configuration information to give a detailed answer." > Hum...what information would you need to understand it better? I can > try to draw an ASCII picture of the network diagram if you need me > to. No, I think that was enough for now. > "But, the short answer is 'run an R2 configuration with pingd > properly configured for your problem'" I looked at this for awhile > and I can't figure out what you mean by "R2." I mean a "crm yes" configuration. > Also, on my heartbeat configuration right now, i'm using "crm no" to > use ipfail, as I found on the mailing list that someone said that > ipfail doesn't work with crm. Does CRM include a replacement for > ipfail that works better? It's called pingd ;-). I'm not sure that either toolset precisely addresses your problem. What you likely really want is this: If one node is up, run all services there. If both nodes are up, and the two nodes can't talk across the crossover, then: run both services on the machine with better connectivity to your clients It's the dual-connectivity test that you'd really like to have that pingd won't really handle. I believe that pingd treats all ping nodes the same. But, to truly solve this problem, you need to treat outside ping nodes differently from inside ping nodes. You _can_ solve the problem in R2, you'll just have to write your own pingd replacement - since it doesn't have to be general, it'll be easy enough to write, but you'll still have to do it... You could do it all in the shell if you like... Then you only tell heartbeat about one of the sets of ping nodes, and not the other set, and your tool would manage the other set. But, none of this is likely to make much sense to you unless you understand the CRM's way of doing things through the rules in the CIB. This is explained in some detail in my tutorial on R2. It's the newest tutorial in the http://linux-ha.org/HeartbeatTutorials page on the web site. The relevant section is slides 137-145. If you haven't used R2 at all, then maybe reviewing the presentation from the beginning would be good. There is a 90 minute video covering some basic things -- given from these slides - and it's linked to from that same page. If you have trouble viewing the video directly, then try the abstract page - it has an embedded video viewer in Java at the bottom of the web page. -- Alan Robertson <[EMAIL PROTECTED]> "Openness is the foundation and preservative of friendship... Let me claim from you at all times your undisguised opinions." - William Wilberforce ___ Linux-HA mailing list Linux-HA@lists.linux-ha.org http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
Re: [Linux-HA] How to set this up correctly...?
Thank you for the link. I'll go through the video and slide show. I'm wondering if what I need would be STONITH...I never got that configured. I'll go through the slide show first before posting up more questions, as it may answer what I need in there. Thanks for all the help! :) >>> On 3/27/2007 at 12:39 PM, Alan Robertson <[EMAIL PROTECTED]> wrote: Howard Yuan wrote: > "Why does the service die when the crossover breaks?" Because I was > planning on telling the services to look for MySQL on 10.0.0.5 (the > floating IP) and if the crossover link breaks, the systems don't know > how to get to 10.0.0.5 as they're looking to find it via the > crossover link (LAN 2). OK. I understand that. So, mysql needs connectivity via the crossover cable. > "I need more configuration information to give a detailed answer." > Hum...what information would you need to understand it better? I can > try to draw an ASCII picture of the network diagram if you need me > to. No, I think that was enough for now. > "But, the short answer is 'run an R2 configuration with pingd > properly configured for your problem'" I looked at this for awhile > and I can't figure out what you mean by "R2." I mean a "crm yes" configuration. > Also, on my heartbeat configuration right now, i'm using "crm no" to > use ipfail, as I found on the mailing list that someone said that > ipfail doesn't work with crm. Does CRM include a replacement for > ipfail that works better? It's called pingd ;-). I'm not sure that either toolset precisely addresses your problem. What you likely really want is this: If one node is up, run all services there. If both nodes are up, and the two nodes can't talk across the crossover, then: run both services on the machine with better connectivity to your clients It's the dual-connectivity test that you'd really like to have that pingd won't really handle. I believe that pingd treats all ping nodes the same. But, to truly solve this problem, you need to treat outside ping nodes differently from inside ping nodes. You _can_ solve the problem in R2, you'll just have to write your own pingd replacement - since it doesn't have to be general, it'll be easy enough to write, but you'll still have to do it... You could do it all in the shell if you like... Then you only tell heartbeat about one of the sets of ping nodes, and not the other set, and your tool would manage the other set. But, none of this is likely to make much sense to you unless you understand the CRM's way of doing things through the rules in the CIB. This is explained in some detail in my tutorial on R2. It's the newest tutorial in the http://linux ( http://linux/ )-ha.org/HeartbeatTutorials page on the web site. The relevant section is slides 137-145. If you haven't used R2 at all, then maybe reviewing the presentation from the beginning would be good. There is a 90 minute video covering some basic things -- given from these slides - and it's linked to from that same page. If you have trouble viewing the video directly, then try the abstract page - it has an embedded video viewer in Java at the bottom of the web page. -- Alan Robertson <[EMAIL PROTECTED]> "Openness is the foundation and preservative of friendship... Let me claim from you at all times your undisguised opinions." - William Wilberforce ___ Linux-HA mailing list Linux-HA@lists.linux-ha.org http://lists.linux ( http://lists.linux/ )-ha.org/mailman/listinfo/linux-ha See also: http://linux ( http://linux/ )-ha.org/ReportingProblems -- Howard Yuan I.T. Department Valence Technology, Inc. http://www.valence.com/ ___ Linux-HA mailing list Linux-HA@lists.linux-ha.org http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
