vRack for two servers doesn't work anymore

Hello everyone,

I use(d) two servers (a dedicated one and a VM) in a vRack. Now there was a hardware intervention (memory upgrade) and since then the two servers cannot communicate anymore, even pings fail. The network setup has not been changed from my side. Any idea what could have gone wrong or how I could debug this?

Server A: Oracle Linux 8.6, 10.0.1.100, attached to vRack
Server B: Ubuntu 22, 10.0.1.209, attached to vRack

serverA$ ping 10.0.1.100
PING 10.0.1.100 (10.0.1.100) 56(84) bytes of data.
From 10.0.1.209 icmp_seq=1 Destination Host Unreachable