Re: [mod_cluster-dev] Session temporarily unavailable

+1. The MCMP SUSPECT should get a response informing what suspected nodes are/aren't still alive. That information can then be made available to management tools. Bela Ban wrote: > > Paul Ferraro wrote: >>>> If you are running mod_cluster via HAModClusterService and node1 crashed >>>> (instead of a clean shut down), node2 will not send any MCMP messages to >>>> httpd on behalf of node1 when it receives a view change. >>> Ah, yes, I remember now ! I just killed -9 node1 and mod-cluster-manager >>> didn't remove node1 from its worker list. >>> >>> Why don't we do this ? We cannot rely on a node being shutdown >>> gracefully ! >> Because currently a given node cannot distinguish between a crashed >> member and a network partition > > OK, so {A,B} would remove C and D and {C,D} would remove A and B... > > How about we send an MCMP SUSPECT message to httpd ? This would cause > httpd to double-check, e.g. via the regular AJP cping/cpong or socket > connection checks, and if the doube-check fails, remove a worker ? > > For the regular case (a crash), this would be faster than having to wait > until httpd checks the connection. > > So a view change would be nothing else than trigger an immediate > connection check on httpd.