RE: High Availability Samba file Server- Piranha FOS+DRBD

              Hi Ed,

                 It's great to see your explanation.Thanks a lot. I think I could make this solution work if I get 
                 the patch from Sebastien.Please assist me for this.

             Thanks&regards,
              Sumesh 
  -----Original Message-----
  From: [email protected] [mailto:[email protected]]On Behalf Of Edward Croft
  Sent: Friday, July 25, 2003 7:17 PM
  To: Piranha List
  Subject: RE: High Availability Samba file Server- Piranha FOS+DRBD


  On Fri, 2003-07-25 at 09:22, Sumesh wrote: 
 Sorry, I am not clear. Can I understand that , at the moment I can't go for Piranha FOS 
 for a HA Samba Fileserver failover  solution ?

Kindly clarify


Thanks&regards
Sumesh
<clip>
  In its default configuration, piranha uses a test to http to see if the other box is online. If you needed more robust testing like actually making sure you could get to the samba shares, you would have to create the test scripts yourself. However, piranha straight out of the box does not support failover script testing, it does for lvs which is where you have a virtual server that dishes out requests to slave boxes. That isn't what you are looking for though, if I read you right. I think you are trying to get what I have running, where you have pairs of boxes, a master and a slave. When the master dies, stops responding, or other malady, the slave detects it and takes over. To the outside world it appears as if the box is still up. Red Hat out of the box, does not really support this scenario, even though they have built in FOS, they go more for clustering and indeed seem to have abandoned piranha in favour of cluster manager. 
  In my configuration, I have fw-fw, app server-app server, and postgres-postgres pairs. The firewalls hold the external shared address and failover that address on a firewall shutdown. The firewalls forward requests to the app server shared address. If the app is down then it fails over to the backup server. This is one place where just testing for http access would not work as this box uses jboss also and that can hang while http still runs,  so more intricate testing is involved. I found out at this time that FOS did not support running external scripts, only in LVS mode. Fortunately, Sebastien had patched piranha to allow for this. It works great, but the caveat is that it isn't stock Red Hat. I have forwarded Sebastien's patches on to Red Hat for possible inclusion in future versions of piranha if they have not abandoned it all together. Oh, for the postgres servers we run an external script that actually attempts to retrieve data to ensure that the database is indeed up and available. 
  I don't know why Red Hat didn't include this capability in the stock piranha. Hopefully, they will. 
  Hope that didn't muddy the waters even further.
  Ed