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vmk0 management network MAC address is not updated when NIC card is replaced or vmkernel has duplicate MAC address (1031111)
- The MAC address of vmk0 management network might not get updated after you replace or assign a new MAC address to the NIC and run the esxcfg-vmknic –l command from the service console. The default setting for the ESXi host is not to select the new hardware MAC address.
- The management network in inaccessible on an ESXi host.
- Unable to ping vmkernel.
- Unable to ping a decommissioned ESXi physical server that has been rebuilt.
- Under certain circumstances there may be a situation where a duplicate mac address arises on the network due to ESXi vmkernel maintaining the mac address of a previous ESXi installation on a different physical server.
- During initial install on the previous server vmkernel vmk0 interface will use the use the physical server's mac address assigned to one of the vmnic interfaces instead of a random 00:50:56::XX:XX:XX.
- On decommissioning the server if the installation USB or Local disk is moved to another server or copied if a LUN, the vmkernel vmk0 interface on the new server will still have the previous server's physical MAC address.
Confirm by checking the physical MAC address of all physical NICs and their link status, the existing vSwitch configuration, and the current vmkernel interfaces configuration. For ESXi, use these commands:
# esxcfg-nics -l
# esxcfg-vswitch -l
# esxcfg-vmknic -l
If a duplicate MAC address is confirmed, the MAC address must be changed by deleting and recreating the vmkernel interface.
To delete a vmknic from a port group, use this command:
# esxcfg-vmknic -d -p pgName
# esxcfg-vmknic -d pgName
To add a vmknic to a port group, use this command:
# esxcfg-vmknic -a -i DHCP -p pgName
# esxcfg-vmknic -a -i x.x.x.x -n 255.255.255.0 pgName
Work around the issue by manually configuring the MAC address on the ESXi host as follows:
- In the troubleshooting console, run this command:
esxcfg-advcfg -s 1 /Net/FollowHardwareMac
- Restart the ESXi server.
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