On 06/27/2013 05:43 PM, Yair Zaslavsky wrote: > > > ----- Original Message ----- >> From: "Eli Mesika" <emes...@redhat.com> >> To: "Martin Perina" <mper...@redhat.com> >> Cc: engine-devel@ovirt.org, "Yair Zaslavsky" <yzasl...@redhat.com>, "Barak >> Azulay" <bazu...@redhat.com> >> Sent: Thursday, June 27, 2013 3:48:39 PM >> Subject: Re: SSH Soft Fencing >> >> >> >> ----- Original Message ----- >>> From: "Martin Perina" <mper...@redhat.com> >>> To: engine-devel@ovirt.org >>> Cc: "Yair Zaslavsky" <yzasl...@redhat.com>, "Barak Azulay" >>> <bazu...@redhat.com>, "Eli Mesika" <emes...@redhat.com> >>> Sent: Thursday, June 27, 2013 1:51:06 PM >>> Subject: SSH Soft Fencing >>> >>> Hi, >>> >>> SSH Soft Fencing is a new feature for 3.3 and it tries to restart VDSM >>> using SSH connection on non responsive hosts prior to real fencing. >>> More info can be found at >>> >>> http://www.ovirt.org/Automatic_Fencing#Automatic_Fencing_in_oVirt_3.3 >>> >>> In current SSH Soft Fencing implementation the restart VDSM using SSH >>> command is part of standard fencing implementation in >>> VdsNotRespondingTreatmentCommand. But this command is executed only >>> if a host has a valid PM configuration. If host doesn't have a valid >>> PM configuration, the execution of the command is disabled and host >>> state is change to Non Responsive. >>> >>> So my question are: >>> >>> 1) Should SSH Soft Fencing be executed on hosts without valid PM >>> configuration? >> >> I think that the answer should be yes. The vdsm restart will solve most of >> problems , so why not using it whether a PM agent is defined or not. > I agree. > I would like to say that I also don't like the fact that > VdsNotRespondingTreatment extends RestartVdsCommand. > One should ask if "non responding treatment is a restart vds operation" or > maybe RestartVdsCommand is just a step in the non responding treatment > (inheritance vs containment/delegation). > I think that VdsNotRespodingTreatment should delegate the call to > RestartVdsCommand as the 2nd step after issuing the Soft Fencing command. > Thoughts anyone? >
I agree. The purpose of this feature is to add escalation step when handling non responsive host. Power fencing is only a step in the escalation flow. so should be called from within the main flow controller (the VdsNotRespodingTreatment). Maybe we'd like this to be fine tuned by a custom policy in future versions. >> >>> >>> 2) Should VDSM restart using SSH command be reimplemented >>> as standalone command to be usable also in other parts of engine? >>> If 1) is true, I think it will have to be done anyway. > > I agree here. >> >> +1 +1 The VDSM restart is a step in the escalation flow, and it should not be tightly coupled with the non-responsive treatment implementation. >> >>> >>> >>> Martin Perina >>> >> > _______________________________________________ > Engine-devel mailing list > Engine-devel@ovirt.org > http://lists.ovirt.org/mailman/listinfo/engine-devel > > _______________________________________________ Engine-devel mailing list Engine-devel@ovirt.org http://lists.ovirt.org/mailman/listinfo/engine-devel
