-----Ursprüngliche Nachricht----- Von: Dejan Muhamedagic <deja...@fastmail.fm> Gesendet: Sep 16, 2010 4:30:37 PM An: High-Availability Linux Development List <linux-ha-dev@lists.linux-ha.org> Betreff: Re: [Linux-ha-dev] Patch for db2 Resource agent
>Hi, > >On Thu, Sep 16, 2010 at 03:32:43PM +0200, Holger Teutsch wrote: >> -----Ursprüngliche Nachricht----- >> >> >On Thu, Sep 16, 2010 at 10:07:49AM +0200, Holger Teutsch wrote: >> >> Hi, >> >> find attached a patch for the db2 resource agent >> >> - holger >> >> >> >> High: Replace call to db2_local_ps with db2nps (Thanx to Evgeny Nifontov) >> >> >> >> db2nodes.cfg typically contains a cluster service address and >> >> db2_local_ps never works >> >> in this case. >> > >> >Is there any documentation or source to support this? Looking at >> >the source, db2_local_ps should recover the right node number >> >from db2nodes.cfg in case that file exists, then invoke db2nps >> >with that node number. If it doesn't work, then it is a bug in >> >db2_local_ps. >> > >> >Cheers, >> > >> >Dejan >> >> Dejan, >> the background is: >> >> db2nodes.cfg maps "partition numbers" to "node names" >> Normally this is the physical hostname. >> >> Most db2 utilities (e.g. db2start etc) map the node number to the "node >> name". >> If "node name" == "uname -n" call locally, else invoke the >> command on the remote host via rsh or something you set via >> >> db2set DB2RSHCMD=xxx >> . >> >> On a cluster the file ~/sqllib/db2nodes.cfg is on a shared FS. >> >> If this file contains a physical hostname this will definitely be wrong >> after a resource migration. >> >> Therefore per best practice (IBM Redbooks etc.) you put the DNS >> name of the cluster service into db2nodes.cfg. >> >> You then have to take care that the instance owner has rsh access to itself >> via the service address. >> Else you can map DB2RSHCMD to a script like >> >> --- >> #!/bin/sh >> # >> # Emulate inter partition call for ACC by simply do it locally >> # Install with >> # >> # db2set DB2RSHCMD=$INSTHOME/db2_acc_rsh >> # >> # HT Dec 2007 >> >> # Is called rsh like as >> # c36db.hg.fresenius.de -n -l db2c36 ARGS >> >> # remove 4 first args >> shift >> shift >> shift >> shift >> eval "$@" >> ---- >> >> Other methods for working with db2nodes.cfg are >> - make links to node local files (problems with permissions) >> - edit db2nodes.cfg with the resource agent prior to an (something a IBM >> povide lib does/tries) >> >> You see we are veterans with 100+ db2 databases. 8-) or 8-( >> >> I agree that the logic of db2_local_ps is to simple to deal with this setup. >> On the other hand I'm not confident that IBM will implement a comprehensive >> way to detect "locality" for a general multi partition setup. >> This would require checking IP interfaces etc... >> >> I checked that db2nps works on DB2 8.2, 9.5 and 9.7. >> >> Any concerns let me know. > >My only concern is that 0 may not be the right node number for >the local node. On failover or failback or whenever. That's why >I'd expect db2_local_ps to be the right way to go. Of course, I >do understand that things don't always work as advertised and in >particular with products such as db2 :) At any rate, if you're >sure that "db2nps 0" is always going to refer to the local node, >then we can go ahead with this change. > >Cheers, > >Dejan > Dejan, in a single partition database the single partition is always "0". db2nps NN looks on the *local* node for processes of partition "NN" i.e. db2nps 0 does the required work. So I think that's OK. Regards Holger ___________________________________________________________ GRATIS: Spider-Man 1-3 sowie 300 weitere Videos! Jetzt kostenlose Movie-FLAT freischalten! http://movieflat.web.de _______________________________________________________ Linux-HA-Dev: Linux-HA-Dev@lists.linux-ha.org http://lists.linux-ha.org/mailman/listinfo/linux-ha-dev Home Page: http://linux-ha.org/
