Extended Attributes (xattr)
|This document is only valid when using Infinite Scale version 2.0. Starting with version 3.0, Infinite Scale has switched to the messagepack backend for metadata.|
Check xattr Support
- Check if extended attributes are supported if selected as metadata backend
When selecting the
xattrs backend for storing metadata, the used POSIX-compliant filesystem from the tables above must support it. You can check this with the following commands, change to a location in the mounted filesystem you want to check before:
touch foo.txt && attr -s mix -V bar foo.txt
Attribute "mix" set to a 3 byte value for foo.txt: bar
attr -g mix foo.txt
Attribute "mix" had a 3 byte value for foo.txt: bar
- NFS Notes
When using NFS and the
xattrsbackend, you have to take care that the NFS server AND the NFS client provides
- NFS Storage Based on Linux Servers
When using a kernel version 5.9 or higher, extended attributes for the NFS server and the NFS client are part of the system. To check, run the command:
On the system providing the NFS server AND on the NFS client check the displayed version number.
- NFS Client
If you have an NFS server capable of extended attributes but you are unsure if your client accessing the server supports it, check the nfs-utils or nfs-common package version of your NFS client with the command:
You need at minimum NFS version 2.6.1. For more details see the general NFS Utils Release History and the Ubuntu nfs-common Packages.
- NFS Servers Provided from Storage Vendors
A certification matrix will be provided when available.
- NFS Protocol Version
Note that if the kernel or the storage system supports extended attributes, you have to use NFSv4 in order to use it.