<div dir="ltr"><div>Hello community!</div><div>I'm not sure if pacemaker can do it or not with current logic (maybe it could be a new feature), but it's worth asking before starting to "<span>build my own <em>Luna</em>-<em>park</em> ,with <em>blackjack</em> and</span> ...."<br></div><div><br></div><div><b>Right now</b> I have something like:<br></div><div>
<div>MGS -> MDT -> OST</div><div>order mdt-after-mgs<b> Optional</b>: mgs:start mdt:start</div><div>
order ost-after-mgs <b>Optional</b>: mgs:start ost:start</div><div>
order ost-after-mdt0000 <b>Optional</b>: mdt0000:start ost:start</div>
</div><div><ul><li>We have 4 nodes (A,B,C,D).<br></li><li>Nodes A and B carry MGS.</li><li>Nodes A,B,C,D carry MDT000[0-3] - one per node.</li><li>
Nodes A,B,C,D carry OST000[0-3] - one per node.</li><li>If we stop nodes A and B, MGS will be stopped since there is NO placement to start for it, but MDT000[0-1] and
OST000[0-1] could failover and will try to do that and will fail since MGS is a mandatory for us (and by the end will be blocked), <b>but I use optional to avoid unnecessary stop/start chain for MDT/OST</b>.<br></li></ul></div><div>
<b>I want to avoid unnecessary STOP/START actions of each dependent
resource in case of failover, but preserve the order and
enforce MGS dependency for those resources which are stopped (so, to start I need to follow the chain and if started then do nothing). Th</b><b>ink about it like separate procedures
for 1st start and failover during work... like soft-mandatory or something like that.</b>
</div><div><br></div><div>I think that if I tweak OCF start/stop (make them dummy and always success) and move all logic to monitors with deep checks, so that monitor could mount/umount and etc. + assign transient attrs which could track ready or not for start, and create location rules which prefer/honor transient attrs, then I could achieve desirable state, but it looks very complex and probably doesn't worth it...</div><div><br></div><div>I would love to see any thoughts about it.</div><div><br></div><div>Thanks,</div><div>A<br></div><div><br></div></div>