Dňa 14.12.2011 1:14, Eric Blake wrote / napísal(a):
Hmm, wondering about back-compat - what happens if we are talking to an older libvirt that does not know VIR_DOMAIN_CONSOLE_FORCE, but also which does not prevent multiple connections when flags==0? At first glance, it looks like we're stuck - there's no useful way to tell if a console was already in use.
Yes, we would end up in a state like when you try it now.
But maybe we could add a new API, to allow probing whether a console is in use. If the API exists, then we know whether the console is in use (and we also know whether --force will work); if the API does not exist, the we know we are talking to an older server that multiplexes connections. Maybe we should have: virsh console domain --safe => refuse to connect unless connection is safe (fails on older servers) virsh console domain --force => force connection (fails on older servers) virsh console domain => existing behavior (connects on older servers, even if it corrupts connection, and safely connects on newer servers)
Yes, that's definitely a good idea.
that is, I'm thinking it might be worth it to add a new --safe option that lets the user probe (via a new API virDomainConsoleInUse(dom, dev_name, flags)) whether the attempt will be safe.
I was thinking about adding another flag. With that flag specified, the virDomainConsoleOpen function would return success without any operation, confirming, that the server is capable of handling console connections in a safe way. The client could then open the connection calling this function again.
What do you think about this option? Peter -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list