[ClusterLabs] Interface confusion

Adam Budziński budzinski.adam at gmail.com
Sat Mar 16 06:10:57 EDT 2019


Hello Andrei,

Ok I see your point. So per my understanding if the resource is started
successfully in that case fence vmware it will be monitored indefinitely
but as you sad it will monitor the current active node. So how does the
fence agent gets aware of problems with the slave? I mean if in a two node
cluster the cluster splits in to two partitions each of them will fence the
other or does that happen because both will assume they are the only
survivors and thus need to fence the other node which is in a unknow state
so to say?

Thank you and Best Regards,
Adam

sob., 16.03.2019, 07:17 użytkownik Andrei Borzenkov <arvidjaar at gmail.com>
napisał:

> 16.03.2019 9:01, Adam Budziński пишет:
> > Thank you Andrei. The problem is that I can see with 'pcs status' that
> > resources are runnin on srv2cr1 but its at the same time its telling that
> > the fence_vmware_soap is running on srv1cr1. That's somewhat confusing.
> > Could you possibly explain this?
> >
>
> Two points.
>
> It is actually logical to have stonith agent running on different node
> than node with active resources - because it is the *other* node that
> will initiate fencing when node with active resources fails.
>
> But even considering the above, active (running) state of fence (or
> stonith) agent just determines on which node recurring monitor operation
> will be started. The actual result of this monitor operation has no
> impact on subsequent stonith attempt and serves just as warning to
> administrator. When stonith request comes, agent may be used by any node
> where stonith agent is not prohibited to run by (co-)location rules. My
> understanding is that this node is selected by DC in partition.
>
> > Thank you!
> >
> > sob., 16.03.2019, 05:37 użytkownik Andrei Borzenkov <arvidjaar at gmail.com
> >
> > napisał:
> >
> >> 16.03.2019 1:16, Adam Budziński пишет:
> >>> Hi Tomas,
> >>>
> >>> Ok but how then pacemaker or the fence agent knows which route to take
> to
> >>> reach the vCenter?
> >>
> >> They do not know or care at all. It is up to your underlying operating
> >> system and its routing tables.
> >>
> >>> Btw. Do I have to add the stonith resource on each of the nodes or is
> it
> >>> just enough to add it on one as for other resources?
> >>
> >> If your fencing agent can (should) be able to run on any node, it should
> >> be enough to define it just once as long as it can properly determine
> >> "port" to use on fencing "device" for a given node. There are cases when
> >> you may want to restrict fencing agent to only subset on nodes or when
> >> you are forced to set unique parameter for each node (consider IPMI IP
> >> address), in this case you would need separate instance of agent in each
> >> case.
> >>
> >>> Thank you!
> >>>
> >>> pt., 15.03.2019, 15:48 użytkownik Tomas Jelinek <tojeline at redhat.com>
> >>> napisał:
> >>>
> >>>> Dne 15. 03. 19 v 15:09 Adam Budziński napsal(a):
> >>>>> Hello Tomas,
> >>>>>
> >>>>> Thank you! So far I  need to say how great this community is, would
> >>>>> never expect so much positive vibes! A big thank you your doing a
> great
> >>>>> job!
> >>>>>
> >>>>> Now let's talk business :)
> >>>>>
> >>>>> So if pcsd is using ring0 and it fails will ring1 not be used at all?
> >>>>
> >>>> Pcs and pcsd never use ring1, but they are just tools for managing
> >>>> clusters. You can have a perfectly functioning cluster without pcs and
> >>>> pcsd running or even installed, it would be just more complicated to
> set
> >>>> it up and manage it.
> >>>>
> >>>> Even if ring0 fails, you will be able to use pcs (in somehow limited
> >>>> manner) as most of its commands don't go through network anyway.
> >>>>
> >>>> Corosync, which is the actual cluster messaging layer, will of course
> >>>> use ring1 in case of ring0 failure.
> >>>>
> >>>>>
> >>>>> So in regards to VMware that would mean that the interface should be
> >>>>> configured with a network that can access the  vCenter to fence
> right?
> >>>>> But wouldn't it then use only ring0 so if that fails it wouldn't
> switch
> >>>>> to ring1?
> >>>>
> >>>> If you are talking about pcmk_host_map, that does not really have
> >>>> anything to do with network interfaces of cluster nodes. It maps node
> >>>> names (parts before :) to "ports" of a fence device (parts after :).
> >>>> Pcs-0.9.x does not support defining custom node names, therefore node
> >>>> names are the same as ring0 addresses.
> >>>>
> >>>> I am not an expert on fence agents / devices, but I'm sure someone
> else
> >>>> on this list will be able to help you with configuring fencing for
> your
> >>>> cluster.
> >>>>
> >>>>
> >>>> Tomas
> >>>>
> >>>>>
> >>>>> Thank you!
> >>>>>
> >>>>> pt., 15.03.2019, 13:14 użytkownik Tomas Jelinek <tojeline at redhat.com
> >>>>> <mailto:tojeline at redhat.com>> napisał:
> >>>>>
> >>>>>     Dne 15. 03. 19 v 12:32 Adam Budziński napsal(a):
> >>>>>      > Hello Folks,____
> >>>>>      >
> >>>>>      > __ __
> >>>>>      >
> >>>>>      > Tow node active/passive VMware VM cluster.____
> >>>>>      >
> >>>>>      > __ __
> >>>>>      >
> >>>>>      > /etc/hosts____
> >>>>>      >
> >>>>>      > __ __
> >>>>>      >
> >>>>>      > 10.116.63.83    srv1____
> >>>>>      >
> >>>>>      > 10.116.63.84    srv2____
> >>>>>      >
> >>>>>      > 172.16.21.12    srv2cr1____
> >>>>>      >
> >>>>>      > 172.16.22.12    srv2cr2____
> >>>>>      >
> >>>>>      > 172.16.21.11    srv1cr1____
> >>>>>      >
> >>>>>      > 172.16.22.11    srv1cr2____
> >>>>>      >
> >>>>>      > __ __
> >>>>>      >
> >>>>>      > __ __
> >>>>>      >
> >>>>>      > I have 3 NIC’s on each VM:____
> >>>>>      >
> >>>>>      > __ __
> >>>>>      >
> >>>>>      > 10.116.63.83    srv1  and 10.116.63.84    srv2 are networks
> used
> >>>> to
> >>>>>      > access the VM’s via SSH or any resource directly if not via a
> >>>>>     VIP.____
> >>>>>      >
> >>>>>      > __ __
> >>>>>      >
> >>>>>      > Everything with cr in its name is used for corosync
> >>>>>     communication, so
> >>>>>      > basically I have two rings (this are two no routable networks
> >>>>>     just for
> >>>>>      > that).____
> >>>>>      >
> >>>>>      > __ __
> >>>>>      >
> >>>>>      > My questions are:____
> >>>>>      >
> >>>>>      > __ __
> >>>>>      >
> >>>>>      > __1.__With ‘pcs cluster auth’ which interface / interfaces
> >> should
> >>>>>     I use
> >>>>>      > ?____
> >>>>>
> >>>>>     Hi Adam,
> >>>>>
> >>>>>     I can see you are using pcs-0.9.x. In that case you should do:
> >>>>>     pcs cluster auth srv1cr1 srv2cr1
> >>>>>
> >>>>>     In other words, use the first address of each node.
> >>>>>     Authenticating all the other addresses should not cause any
> issues.
> >>>> It
> >>>>>     is pointless, though, as pcs only communicates via ring0
> addresses.
> >>>>>
> >>>>>      >
> >>>>>      > __2.__With ‘pcs cluster setup –name’ I would use the corosync
> >>>>>     interfaces
> >>>>>      > e.g. ‘pcs cluster setup –name MyCluster srv1cr1,srv1cr2
> >>>>>     srv2cr1,srv2cr2’
> >>>>>      > right ?____
> >>>>>
> >>>>>     Yes, that is correct.
> >>>>>
> >>>>>      >
> >>>>>      > __3.__With fence_vmware_soap
> >> inpcmk_host_map="X:VM_C;X:VM:OTRS_D"
> >>>>>     which
> >>>>>      > interface should replace X ?____
> >>>>>
> >>>>>     X should be replaced by node names as seen by pacemaker. Once you
> >>>>>     set up
> >>>>>     and start your cluster, run 'pcs status' to get (amongs other
> info)
> >>>> the
> >>>>>     node names. In your configuration, they should be srv1cr1 and
> >>>> srv2cr1.
> >>>>>
> >>>>>
> >>>>>     Regards,
> >>>>>     Tomas
> >>>>>
> >>>>>      > __ __
> >>>>>      >
> >>>>>      > Thank you!
> >>>>>      >
> >>>>>      >
> >>>>>      > _______________________________________________
> >>>>>      > Users mailing list: Users at clusterlabs.org
> >>>>>     <mailto:Users at clusterlabs.org>
> >>>>>      > https://lists.clusterlabs.org/mailman/listinfo/users
> >>>>>      >
> >>>>>      > Project Home: http://www.clusterlabs.org
> >>>>>      > Getting started:
> >>>>>     http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> >>>>>      > Bugs: http://bugs.clusterlabs.org
> >>>>>      >
> >>>>>     _______________________________________________
> >>>>>     Users mailing list: Users at clusterlabs.org <mailto:
> >>>> Users at clusterlabs.org>
> >>>>>     https://lists.clusterlabs.org/mailman/listinfo/users
> >>>>>
> >>>>>     Project Home: http://www.clusterlabs.org
> >>>>>     Getting started:
> >>>> http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> >>>>>     Bugs: http://bugs.clusterlabs.org
> >>>>>
> >>>>>
> >>>>> _______________________________________________
> >>>>> Users mailing list: Users at clusterlabs.org
> >>>>> https://lists.clusterlabs.org/mailman/listinfo/users
> >>>>>
> >>>>> Project Home: http://www.clusterlabs.org
> >>>>> Getting started:
> >> http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> >>>>> Bugs: http://bugs.clusterlabs.org
> >>>>>
> >>>> _______________________________________________
> >>>> Users mailing list: Users at clusterlabs.org
> >>>> https://lists.clusterlabs.org/mailman/listinfo/users
> >>>>
> >>>> Project Home: http://www.clusterlabs.org
> >>>> Getting started:
> >> http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> >>>> Bugs: http://bugs.clusterlabs.org
> >>>>
> >>>
> >>>
> >>> _______________________________________________
> >>> Users mailing list: Users at clusterlabs.org
> >>> https://lists.clusterlabs.org/mailman/listinfo/users
> >>>
> >>> Project Home: http://www.clusterlabs.org
> >>> Getting started:
> http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> >>> Bugs: http://bugs.clusterlabs.org
> >>>
> >>
> >> _______________________________________________
> >> Users mailing list: Users at clusterlabs.org
> >> https://lists.clusterlabs.org/mailman/listinfo/users
> >>
> >> Project Home: http://www.clusterlabs.org
> >> Getting started:
> http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> >> Bugs: http://bugs.clusterlabs.org
> >>
> >
> >
> > _______________________________________________
> > Users mailing list: Users at clusterlabs.org
> > https://lists.clusterlabs.org/mailman/listinfo/users
> >
> > Project Home: http://www.clusterlabs.org
> > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> > Bugs: http://bugs.clusterlabs.org
> >
>
> _______________________________________________
> Users mailing list: Users at clusterlabs.org
> https://lists.clusterlabs.org/mailman/listinfo/users
>
> Project Home: http://www.clusterlabs.org
> Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> Bugs: http://bugs.clusterlabs.org
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.clusterlabs.org/pipermail/users/attachments/20190316/2e45de3b/attachment-0001.html>


More information about the Users mailing list