Hello @MajorP93,
Several things in your message raise questions for me.
First, this SR:
1x Linstor vSAN iSCSI configured as QCOW2
What is this storage and how is it configured?
Currently, we do not support QCOW2 on Linstor/Xostor. So, is it simply an iSCSI device to which you have applied the QCOW2 format, or is it a Xostor on the XCP-ng pool?
Regarding jumbo frames, we do not use them internally and are not currently testing them. It is often recommended not to use them for the management interface, as indicated in the XCP-ng documentation: https://docs.xcp-ng.org/networking/
Non-standard MTUs (such as jumbo frames) are not supported on management interfaces. Using them can lead to serious issues, including failed pool member joins or unexpected network outages.
Is that the case here?