On 03/21/2013 01:11 PM, Maurizio Giungato wrote:
Hi guys,
my goal is to create a reliable virtualization environment using CentOS 6.4 and KVM, I've three nodes and a clustered GFS2.
The enviroment is up and working, but I'm worry for the reliability, if I turn the network interface down on one node to simulate a crash (for example on the node "node6.blade"):
- GFS2 hangs (processes go in D state) until node6.blade get fenced
- not only node6.blade get fenced, but also node5.blade!
Help me to save my last neurons!
Thanks Maurizio
DLM, the distributed lock manager provided by the cluster, is designed to block when a known goes into an unknown state. It does not unblock until that node is confirmed to be fenced. This is by design. GFS2, rgmanager and clustered LVM all use DLM, so they will all block as well.
As for why two nodes get fenced, you will need to share more about your configuration.