The servers in cluster mounts the cluster filesystem at the same
time with read/write access. If one of the machines is not responding
or is thought to be not functioning well, hence it is important to prevent
this machine from accessing the shared storage or the cluster filesystem.
Hence the action of "fencing" the node. So the goal is to prevent the
node from the I/O path to the storage. This usually happens by different
means. So fence here would refer to isolating the machine or cut the
path to the I/O somehow. I am not sure if isolate is a proper meaning
here, as the goal is to cut really the I/O path either by rebooting the
machine or switching off the SAN port that connect it to the storage.
Not sure if I explained or made it more complicated!
I'm unsure of how to translate the summary for the package
fence - The cluster I/O fencing system
I'me aware of two basic meanings of "fence": a barrier around an area
and a sport involving a old style weapon I believe is called with the
French word épée. Neither quite seems to apply.
I looked at the longer description, but that didn't help me. And
there was no URL to follow.
I'm sure I just miss some nuances here. Could someone with a better
understanding explain to me what?