Fencing is must even if multiple heartbeats are configured

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z_haseeb
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Joined: 2009/12/31 07:58:30

Fencing is must even if multiple heartbeats are configured

Post by z_haseeb » 2017/11/21 10:16:48

Does fencing is must to configure for a 2 nodes HA implemented on RHEL7 with multiple configured heartbeats

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TrevorH
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Re: Fencing is must even if multiple heartbeats are configured

Post by TrevorH » 2017/11/21 10:29:02

Yes.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

z_haseeb
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Joined: 2009/12/31 07:58:30

Re: Fencing is must even if multiple heartbeats are configured

Post by z_haseeb » 2017/11/22 04:32:55

Means we will unable to configure HA without Fencing. I am assuming fencing a prerequisite ?

hunter86_bg
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Re: Fencing is must even if multiple heartbeats are configured

Post by hunter86_bg » 2017/11/23 21:27:11

You can use poison pill (sbd devices + watchdog) , or you can use:

Code: Select all

pcs property set stonith-enabled=false
The second option is highly unrecommended.The sbd device could be a iSCSI or FC LUN,so fencing is an option even in testing environments.

z_haseeb
Posts: 102
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Re: Fencing is must even if multiple heartbeats are configured

Post by z_haseeb » 2017/11/24 10:54:20

Do you recommend / suggest any weblink for first option for fencing ?

hunter86_bg
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Re: Fencing is must even if multiple heartbeats are configured

Post by hunter86_bg » 2017/11/24 16:31:02

I am always checking the red hat solution.
If I don't miss anything it should be something like:
1.Create FC/iSCSI partition of 2MB and present it (if FC)
2.Login all nodes to the iSCSI target independently (no need to define them in the cluster)
3.Install 'sbd' package.
4.Setup(format) sbd devic via 'pcs'
5.Enable sbd service via 'pcs' (if you don't have hardware watchdog - use 'softdog')
6.Create sbd device via which the fencing will happen.

Note:Poison pill (aka sbd) is available since RHEL7.4 and its derivatives.
Redhat have a free developer subscription which provides many stuff including access to their solution database.If you feel fit,you can take advantage of that.

P.S:There is a very nice HA course on safaribooksonline.com.Author is Sander van Vugt.Safari has a free week trial,so you can subscribe and view the course.

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