beardog1113
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linux NFS
Dear all
What happens in NFS if 2 or more servers try to write the same file simultaneously
What happens in NFS if 2 or more servers try to write the same file simultaneously
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That is dependend on the receiving order of packets... That is why there is a lockd (lock deamon) part of the NFS stack so you can claim ownership of something excluding other systems from accessing this at the same time.
Here's a little more information regarding NFS file locking - https://docs.vmware.com/en/VMware-vSphere/6.7/com.vmware.vsphere.storage.doc/GUID-C06E2F04-C3F6-4701-B62E-BCECCEAA7045.html
@ David Favor
Oh? I'm sure that would come as a surprise to a good number of people
@ David Favor
There's a reason NFS is rarely used anymore
Oh? I'm sure that would come as a surprise to a good number of people
@David: NFS is used ... as it follows unix concepts it does fit reasonably well in unix only environments.
Anyway, any shared filsystem will have similar issues, GFS, SAMBA, etc. etc. some coordination esp. on the filesystem is needed, locking is the only way to ensure consistency is possible.
An operating system like OpenVMS demands locking, you have to take effort to try to circumvent it, it has sane defaults therefore there is hardly anything you need to do from a programmers PoV to build clustered systems. If something works concurrently on a multitasking system it will work on a cluster. On OpenVMS clustering is no headache any size of cluster you like, includeing adding / removing ndoes.
Anyway, any shared filsystem will have similar issues, GFS, SAMBA, etc. etc. some coordination esp. on the filesystem is needed, locking is the only way to ensure consistency is possible.
An operating system like OpenVMS demands locking, you have to take effort to try to circumvent it, it has sane defaults therefore there is hardly anything you need to do from a programmers PoV to build clustered systems. If something works concurrently on a multitasking system it will work on a cluster. On OpenVMS clustering is no headache any size of cluster you like, includeing adding / removing ndoes.