On Thu, Nov 07, 2024 at 08:59:30AM +0100, Ferenc Wágner wrote:
> I think a good solution is taking shape here. My thoughts:
>
> 1. Currently pacemaker only Recommends fence-agents, so users disabling
> Recommends must have installed it manually (unless disabled it later).
>
> 2. Using pacemaker without fencing is possible but unsupported, so
> tightening this dependency is reasonable given a singular alternative.
>
> 3. Users creating their own fence agent packages should depend on
> fence-agents-common, or install it manually for plain scripts.
>
> 4. The xserver-xorg-video-* setup is a nice and well-known solution, if
> all stakeholders support this setup, I'd go with it.
>
> 6. I'd avoid having both fence-agents and fence-agents-all, or
> fence-agent and fence-agents (for name similarity). In the end
> pacemaker should contain something like this, I guess:
>
> Depends: fence-agents-all | fence-agent
>
> where fence-agents-all would Depend on all agents (possibly only
> Recommending some esoteric big ones), and all agent packages would
> Provide fence-agents.
>
> Would this handle all concerns? Or should pacemaker stay with only
> Recommending the agents?
Maybe Recommends in pacemaker still fits better with the description:
This declares a strong, but not absolute, dependency.
The Recommends field should list packages that would be found
together with this one in all but unusual installations.
But there might be few other complications to this plan...
For example, fence-agents-sbd can only be in Suggests because will also
install the sbd daemon. That daemon could influence the behavior of the
pacemaker cluster in unexpected ways like rebooting the node when quorum
is lost.
Another problem are the legacy stonith agents in the cluster-glue
package listed left below. Some of them like stonith:external/hetzner
might still be useful if there is no alternative in fence-agents.
But if we have cluster-glue also provide fence-agent, than
fence-agents-all will not be installed by default anymore?
stonith:apcmaster stonith:fence_ilo2
stonith:apcmastersnmp stonith:fence_ilo3
stonith:apcsmart stonith:fence_ilo3_ssh
stonith:baytech stonith:fence_ilo4
stonith:bladehpi stonith:fence_ilo4_ssh
stonith:cyclades stonith:fence_ilo5
stonith:drac3 stonith:fence_ilo5_ssh
stonith:external/drac5 stonith:fence_ilo_moonshot
stonith:external/dracmc-telnet stonith:fence_ilo_mp
stonith:external/hetzner stonith:fence_ilo_ssh
stonith:external/hmchttp stonith:fence_imm
stonith:external/ibmrsa stonith:fence_intelmodular
stonith:external/ibmrsa-telnet stonith:fence_ipdu
stonith:external/ipmi stonith:fence_ipmilan
stonith:external/ippower9258 stonith:fence_ipmilanplus
stonith:external/kdumpcheck stonith:fence_ironic
stonith:external/libvirt stonith:fence_kdump
stonith:external/nut stonith:fence_kubevirt
stonith:external/rackpdu stonith:fence_ldom
stonith:external/riloe stonith:fence_legacy
stonith:external/sbd stonith:fence_lindypdu
stonith:external/ssh stonith:fence_lpar
stonith:external/vcenter stonith:fence_mpath
stonith:external/vmware stonith:fence_netio
stonith:external/xen0 stonith:fence_openstack
stonith:external/xen0-ha stonith:fence_ovh
--
Valentin
