These kind of deployments, are they part of a Linux-HA best practices document? E.g. the kind of backup defense you are using with the PDU is it something of your flavor or is it common practice?
________________________________ From: Digimer <[email protected]> To: Hermes Flying <[email protected]> Cc: General Linux-HA mailing list <[email protected]>; Andrew Beekhof <[email protected]> Sent: Monday, December 3, 2012 2:07 PM Subject: Re: [Linux-HA] Does stonith always succeed? Poorly. Stretch clusters are extremely difficult to build, which is why I do not recommend building them. With few exceptions, tradition remote-backup warm-spare servers is better than stretch clusters. On 12/03/2012 07:05 AM, Hermes Flying wrote: > But this assumes that the servers are co-located, right? How is > geo-separated nodes supported? > > > ------------------------------------------------------------------------ > *From:* Digimer <[email protected]> > *To:* General Linux-HA mailing list <[email protected]> > *Cc:* Andrew Beekhof <[email protected]>; Hermes Flying > <[email protected]> > *Sent:* Monday, December 3, 2012 1:18 PM > *Subject:* Re: [Linux-HA] Does stonith always succeed? > > On 12/03/2012 06:11 AM, Andrew Beekhof wrote: >> On Mon, Dec 3, 2012 at 9:03 PM, Hermes Flying <[email protected] > <mailto:[email protected]>> wrote: >>> Hi, >>> My understanding is that HA using Pacemaker is based on fencing/STONITH . >>> So my question is: Is STONITH guaranteed to ALWAYS succeed? >> >> No. >> >>> Are there cases when it fails? When? E.g. in specific deployments > (example geo-separation)? >> >> Misconfiguration. Hardware failure. Plenty of reasons. >> >>> >>> Thanks > > Nothing is computers is ever 100%. Anyone who tells you otherwise is a > marketing drone. > > This is why, in my clusters, I always use two fence methods; I use IPMI > (or iLO, DRAC, RSA) as the preferred fence device but, if that fails, I > have switched PDUs as backup fence devices. > > A classic way that fencing can fail is, for example, the power feeding a > server fails (like a fried power supply or blown motherboard) which cuts > the power to the IPMI BMC. In this scenario, the IPMI BMC is down and > can't reply to the other node. > > -- > Digimer > Papers and Projects: https://alteeve.ca/w/ > What if the cure for cancer is trapped in the mind of a person without > access to education? > > -- Digimer Papers and Projects: https://alteeve.ca/w/ What if the cure for cancer is trapped in the mind of a person without access to education? _______________________________________________ Linux-HA mailing list [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
