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ZFS is not a distributed filesystem. What you can do is export it over nfs for example. It also has replication features with send/receive but I don't think thi

by spahl 16y ago

ZFS is not a distributed filesystem. What you can do is export it over nfs for example. It also has replication features with send/receive but I don't think this implementation supports it. Edit: I notice that a lot of people think ZFS is a cluster/distributed filesystem. I don't understand where they get this idea.

nivertech 16y ago
Shared filesystem is not the same as cluster/distributed filesystem. It's mere a management convenience and letting legacy code work without changes. There is a problem on Amazon EC2, that you can mount EBS (Elastic Block Storage) only to one EC2 instance at a time. I was told by several people (including some from Sun), that the only way to mount the same EBS instance to multiple EC2 instances is to use OpenSolaris and ZFS. I don't think this solution involves NFS. Anyway now when ZFS almost ported to Linux, it would be great to check this issue again (requires ZPL).
- carson 16y ago
  There is no way of attaching EBS volumes to multiple instances, see the EBS API overview: http://docs.amazonwebservices.com/AWSEC2/2010-08-31/DeveloperGuide/ebs-api-overview.html http://docs.amazonwebservices.com/AWSEC2/2010-08-31/Develope... What might work if you wanted to do this is to mount the EBS volume to an instance and then expose the volume using a network block device to multiple instances. Seems convoluted. Being able to attach EBS to multiple instances may be something Amazon will add if there is enough interest.
- ssmoot 16y ago
  So I'd guess EBS is nothing more than ISCSI targets then. ZFS won't do anything to make those usable on multiple machines at once. ZFS does make it easy to mirror multiple LUNs for redundancy though, so if you have a timeout or permanent disconnect from the device you remain operational. In addition detaching the device and moving it to another machine is trivial with zfs export/import commands.

by spahl 16y ago

nivertech 16y ago

Shared filesystem is not the same as cluster/distributed filesystem. It's mere a management convenience and letting legacy code work without changes. There is a problem on Amazon EC2, that you can mount EBS (Elastic Block Storage) only to one EC2 instance at a time. I was told by several people (including some from Sun), that the only way to mount the same EBS instance to multiple EC2 instances is to use OpenSolaris and ZFS. I don't think this solution involves NFS. Anyway now when ZFS almost ported to Linux, it would be great to check this issue again (requires ZPL).

carson 16y ago
There is no way of attaching EBS volumes to multiple instances, see the EBS API overview: http://docs.amazonwebservices.com/AWSEC2/2010-08-31/DeveloperGuide/ebs-api-overview.html http://docs.amazonwebservices.com/AWSEC2/2010-08-31/Develope... What might work if you wanted to do this is to mount the EBS volume to an instance and then expose the volume using a network block device to multiple instances. Seems convoluted. Being able to attach EBS to multiple instances may be something Amazon will add if there is enough interest.
ssmoot 16y ago
So I'd guess EBS is nothing more than ISCSI targets then. ZFS won't do anything to make those usable on multiple machines at once. ZFS does make it easy to mirror multiple LUNs for redundancy though, so if you have a timeout or permanent disconnect from the device you remain operational. In addition detaching the device and moving it to another machine is trivial with zfs export/import commands.