PowerFlex 3.x: Gateway Analyze System reports "The Virtual IP address does not match the NIC's subnet configuration"

Scenario

The MDM control IP addresses are configured on their associated network interface cards (NICs) with a network prefix which is not divisible by 8. That is, the netmask used is not one of 255.0.0.0 (8-bit network prefix), 255.255.0.0 (16-bit network prefix) or 255.255.255.0 (24-bit network prefix).

Symptoms

In the report generated by the Analyzed System Gateway feature, under the Network section, under MDM Cluster the "The Virtual IP address does not match the NIC's subnet configuration" issue appears.

In the issue details, one or more of the NICs' listed subnet masks do not match those configured on the host and are not valid subnet masks, for example 255.255.63.0.

Impact

System diagnosis fails to correctly identify whether or not an issue exists.

A software issue with the VxFlex OS Gateway, which incorrectly parses some netmasks.

Manually verify that the netmask associated with MDM managers' (primary and secondary) control IP addresses match the netmask of the virtual IP configured on the primary MDM node.
1. On the primary MDM, identify the cluster's virtual IP addresses.

scli --query_cluster |grep 'Virtual IPs'

Sample output:

Virtual IPs: 172.17.232.10, 172.17.240.10

2. For each of the configured virtual IP addresses shown in the previous step, note down the configured network prefix configured on the primary MDM.

ip addr list |grep <mdm virtual ip address>

Example and corresponding output:

# ip addr list |grep 172.17.232.10
    inet 172.17.232.10/22 brd 172.17.235.255 scope global secondary eth1:mdm

In the example above, the network prefix is 22.

3. On the primary MDM, identify the managers' configured control IP addresses and the associated NICs.

scli --query_cluster |grep 'Virtual IP interfaces' 

Sample output:

IPs: 172.17.232.6, 172.17.240.6, Management IPs: 10.234.243.6, Port: 9011, Virtual IP interfaces: eth1, eth2
IPs: 172.17.232.5, 172.17.240.5, Management IPs: 10.234.243.5, Port: 9011, Virtual IP interfaces: eth1, eth2

4. On each of the MDM managers' (primary and secondary) hosts, confirm that the NICs configured for use with the MDM virtual IP addresses are configured with the same network prefix as noted in step 2. All network prefixes are expected to match their virtual IP address counterparts.

ip addr list <interface name> |grep -w inet |grep -v secondary

Example and corresponding output:

# ip addr list eth1 |grep -w inet |grep -v secondary
inet 172.17.232.6/22 brd 172.17.235.255 scope global eth1

Note the displayed network prefix, 22, matches the one noted in the example in step 2.

Impacted Versions

VxFlex OS Gateway 2.x

VxFlex OS Gateway 3.0.x