Hi team, We’re facing a strange issue with network performance on one of our oVirt hosts and would like to get insights or guidance on possible misconfigurations or compatibility problems. Environment Details: oVirt Version: 4.5.5 Cluster CPU Type: Intel IceLake Server Family (default) Host A (Issue observed): CPU: Intel Xeon Platinum 8562Y+ (Sapphire Rapids) CPU Family/Model: Family 6 / Model 207 / Stepping 2 Host B (Working fine): CPU: Intel Xeon Gold 6354 (Ice Lake) CPU Family/Model: Family 6 / Model 106 / Stepping 6 Problem Description: We have a VM (kitsu) that was initially hosted on botovirtnode-006 (Platinum 8562Y+). The VM showed very poor download speeds (~10 Mbps), while upload was fine (~680 Mbps). After migrating the same VM to another host (botovirtnode-001 with Gold 6354 CPU), network performance drastically improved: Test On Affected Node On Healthy Node Download ~10 Mbps ~920 Mbps Upload ~680 Mbps ~760 Mbps This clearly indicates a host-specific issue, most likely related to hardware compatibility or CPU feature masking. Troubleshooting Done: Verified VM configurations (same on both hosts). Tested with speedtest-cli multiple times to confirm. Confirmed that VM virtual NIC, vNIC profile, and vSwitch settings are identical. Both hosts are part of the same cluster using the default Intel IceLake Server CPU type. Suspect the issue is due to CPU feature mismatch or unsupported stepping/model in the cluster’s CPU type.