ESXi Host Intermittently Disconnects from vCenter Server due to IP Address Conflict

Products

• VMware vCenter Server
• VMware vSphere ESXi

Issue/Introduction

• An ESXi Host intermittently disconnects from vCenter Server. The host may not automatically reconnect and might require manual re-connection.
• You may see similar log entries in vCenter log files /var/log/vmware/vpxd/vpxd-####.log

YYYY-MM-DDTHH:MM:SS.SSSZ warning vpxd[ProcessID] [Originator@Subsystem sub=ComponentName opID=OperationID] Host IP address conflict detected. [vim.HostSystem:host-####, YourHostName.YourDomain.com] is trying to change IP from YourHostName.YourDomain.com to ##.##.##.##. New IP is already used by YourHostName.YourDomain.com

Environment

VMware vCenter Server

VMware vSphere ESXi

Cause

Inconsistent or incorrect DNS resolution (forward or reverse) for the ESXi host hostname or IP address prevents vCenter from accurately verifying the host network identity. This often occurs when vCenter Server is unable to correctly resolve the host DNS entries or receives conflicting information from the DNS server.

Resolution

Verify and correct the DNS configuration for the impacted ESXi hosts:

1. Ensure forward and reverse DNS lookups for all ESXi hosts match the configured IP addresses.
2. Flush the DNS cache on the vCenter Server Appliance.
3. If the issue persists, consider adding static entries to the /etc/hosts file on the vCenter Server as a temporary workaround.

For detailed troubleshooting steps, see Resolving ESXi host disconnects caused by DNS resolution failures in vCenter Server.