ESX host may be uncontactable in VirtualCenter when backup Service Console is disconnected

Issue

When testing HA functionallity, disconnecting the backup/redundant Service Console may cause the ESX host to be uncontactable in VirtualCenter although the primary Service Console IP address is still contactable from hosts on the same subnet as the primary Service Console.

Resolution

This would appear to be due to a routing issue in the service console. e.g.

# esxcfg-vswif -l
Name     Port Group              IP Address       Netmask          Broadcast        Enabled   DHCP
vswif0   Service Console         172.16.1.10     255.255.255.0     172.16.1.255     true      false
vswif1   Backup Service Console  172.16.2.10     255.255.255.0     172.16.2.255     true      false


# route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
172.16.1.0     *               255.255.255.0   U     0      0        0 vswif0
172.16.2.0     *               255.255.255.0   U     0      0        0 vswif1
default         172.254.1.1    0.0.0.0         UG    0      0        0 vswif0


VirtualCenter is on the 172.16.2.x network.


To resolve the issue either add a route or use an IP address on a different subnet from VirtualCenter and different from the Service Console.

e.g. Add a route for the VirtualCenter network to the primary Service Console:

route add -net 172.16.2.0 netmask 255.255.255.0 vswif0


Changes can be made permanent by editing /etc/sysconfig/network-scripts/route-vswif0 with the following entries:

ADDRESS0=172.16.2.20
NETMASK0=255.255.255.255
GATEWAY0=172.16.2.1


Test this updates the routing table with either of the following commands:

/etc/sysconfig/network-scripts/ifup-routes vswif0
service network restart


A better solution is to use a separate subnet from the primary Service Console and from VirtualCenter for the backup Service Console e.g. 172.16.3.x

Do not use the same subnet for the primary Service Console and the backup Service Console as this will not function as expected:

VMware ESX High Availability not working as expected
http://theether.net/kb/100041

References

Adding static route to ESX host for extra Service Console
http://kb.vmware.com/kb/1005212

Products

VMware ESX 3.5 Update 1
VMware ESX 3.5
VMware ESX 3.0.2
VMware ESX 3.0.1
VMware ESX 3.0.0

Created: 3rd July 2008
Updated: 5th July 2008


© 2005-2017 Jamie Morrison