The NSX-T Tier-0 Gateway must be configured to have all inactive interfaces removed.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
low	V-251746	SRG-NET-000019-RTR-000007	T0RT-3X-000016	SV-251746r810122_rule	2022-09-01	1

Description
An inactive interface is rarely monitored or controlled and may expose a network to an undetected attack on that interface. If an interface is no longer used, the configuration must be deleted.

ℹ️ Check
From the NSX-T Manager web interface, go to Networking >> Tier-0 Gateways. For every Tier-0 Gateway, expand the Tier-0 Gateway >> Interfaces, and click on the number of interfaces present to open the interfaces dialog. Review each interface present to determine if they are not in use or inactive. If there are any interfaces present on a Tier-0 Gateway that are not in use or inactive, this is a finding.

ℹ️ Check

From the NSX-T Manager web interface, go to Networking >> Tier-0 Gateways. For every Tier-0 Gateway, expand the Tier-0 Gateway >> Interfaces, and click on the number of interfaces present to open the interfaces dialog. Review each interface present to determine if they are not in use or inactive. If there are any interfaces present on a Tier-0 Gateway that are not in use or inactive, this is a finding.

✔️ Fix
Disable multicast PIM routing on interfaces that are not required to support multicast by doing the following: From the NSX-T Manager web interface, go to Networking >> Tier-0 Gateways and expand the target Tier-0 gateway. Expand "Interfaces", then click on the number of interfaces present to open the interfaces dialog. Select "Delete" on the unneeded interface, and then click "Delete" again to confirm.

✔️ Fix

Disable multicast PIM routing on interfaces that are not required to support multicast by doing the following: From the NSX-T Manager web interface, go to Networking >> Tier-0 Gateways and expand the target Tier-0 gateway. Expand "Interfaces", then click on the number of interfaces present to open the interfaces dialog. Select "Delete" on the unneeded interface, and then click "Delete" again to confirm.