Support a shared mount directory as SecondaryStorage with ShareMountPoint type

[hooklee2000]

ISSUE TYPE

• Feature Idea

CLOUDSTACK VERSION

4.15.0

COMPONENT NAME

SecondaryStorage

The existing ShareMountPoint means you would need to mount a clustered filesystem to all the hosts
in the cluster so that multiple hosts can write to the same shared(mountPoint) storage without causing
file system corruption.
In all hosts we use fuse to mount a distribution filesystem to a POSIX directory such as /cfs/share，
which can share files and directories in all hosts.
We can use directory /cfs/share/primary/ as primary storage with ShareMountPoint type now.
Can CloudStack use directory /cfs/share/secondary/ as Secondary Storage with ShareMountPoint type ?

[rohityadavcloud]

Secondary Storage is mounted in the SSVM by the SSVM agent, so it can't be used as mountable directory. You may however mount it on the hypervisor host. Can you explain your use-case wrt secondary storage?

[hooklee2000]

Thanks! We have a distribution file storage system such as Ceph FileSystem, ChubaoFS which can mount a directory in client hosts.
But We prefer fuse mount interface (which support IO_URING) to s3 interface for better read/write performance reason. see #5012
Currently we alse use linux kernel 5.11，qemu5.2.0 and libvirt7.2.0 on CentOS7.4 to enable IO_URING on all hypervisor hosts . We can mount our filesystem to a directory on the SSVM too.
We need also upgrade the linux kernel of the SSVM to kernel 5.11.

[rohityadavcloud]

@hooklee2000 the specific use-case you've described is not supported, maybe @GabrielBrascher @wido @weizhouapache may give you some guidance.

[DaanHoogland]

no activity on this issue, moving it to unplanned

[rohityadavcloud]

This is possible via export a cephfs via nfs. Or using a nfs gw with Ceph.