John R Pierce wrote: > Karl R. Balsmeier wrote: >> How does one configure a fence device in the form of a NIC card in >> centos 5? Is the gnbd item relevant to this? > > I'm not sure what 'a fence device in the form of a NIC card' is. the > fence devices I'm familiar with include SCSI fence switches, > fiberchannel SAN switches, and APC SmartPlug power switches. > > in my test cluster, I used a Qlogic SANbox fiber switch to connect the > cluster nodes to the shared storage. the fencing was done by > sending the Qlogic the commands to enable/disable the ports of the two > nodes so only the active node could access the shared storage. > > I suppose an Ethernet analog in an ISCSI SAN environment would be to > send commands to a layer-2 or layer-3 managed switch to manipulate the > VLANs to disable the standby nodes from accessing the ISCSI target > device. These systems would need separate dedicated NICs for LAN > connectivity and cluster heartbeats. > > OK, so it sounds like I have enough ethernet devices, and your notes help me to understand the purpose and nature of fencing a lot more. I just need to isolate the potential on the iSCSI side of the equation as far as sending those signals to the managed switch. Right now I run on extreme summit switches which should suffice, and broadcomm GBNICs. The iSCSI device we are using is a PromiseRAID M300i or M500i. It sounds on the surface like we might need a more solid fencing device... Anyone agree or disagree? -karl > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos