Hi, colleague.
Sorry for the long reply, I just got out of the hospital after surgery. Everything is fine now.
My colleague checked the tests while I was away. The results are as follows:
1) Enabling jumbo results in a blue screen even if rdma is off.
2) When sr-iov is on in the virtual machine settings, it results in periodic connection failure. It doesn't matter whether rdma or jumbo is on/off. You can move the VM to another node, reboot the VM - the connection appears.
3) During all this time, with jumbo off, there was not a single blue screen.
Unfortunately, we were unable to run tests on old network cards - they were sold.