ARP
The nv unset commands remove the configuration you set with the equivalent nv set commands. This guide only describes an nv unset command if it differs from the nv set command.
nv set interface <interface-id> neighbor ipv4 <ip-address-id> lladdr <lladdr-id>
Configures a static ARP table entry for an interface with an IPv4 address associated with a MAC address for easy management or as a security measure to prevent spoofing and other nefarious activities.
Command Syntax
| Syntax | Description |
|---|---|
<interface-id> |
The interface you want to configure. |
<ip-address-id> |
The static IP address. |
<lladdr-id> |
The MAC address you want to associate with IPv4 address. |
Version History
Introduced in Cumulus Linux 5.7.0
Example
cumulus@switch:~$ nv set interface swp51 neighbor ipv4 10.5.5.51 lladdr 00:00:5E:00:53:51
nv set interface <interface-id> neighbor ipv4 <ip-address-id> lladdr <lladdr-id> flag
Configures a flag to indicate that the neighbor in the ARP table entry is a router (is-router) or learned externally (ext_learn)
Command Syntax
| Syntax | Description |
|---|---|
<interface-id> |
The interface you want to configure. |
<ip-address-id> |
The static IP address. |
<lladdr-id> |
The MAC address you want to associate with IPv4 address. |
Version History
Introduced in Cumulus Linux 5.7.0
Example
cumulus@switch:~$ nv set interface swp51 neighbor ipv4 10.5.5.51 lladdr 00:00:5E:00:53:51 flag is-router
nv set interface <interface-id> neighbor ipv4 <ip-address-id> lladdr <lladdr-id> state
Configures the state of the neighbor in the ARP table entry (delay, failed, incomplete, noarp, permanent, probe, reachable, or stale).
Command Syntax
| Syntax | Description |
|---|---|
<interface-id> |
The interface you want to configure. |
<ip-address-id> |
The static IP address. |
<lladdr-id> |
The MAC address you want to associate with IPv4 address. |
Version History
Introduced in Cumulus Linux 5.7.0
Example
cumulus@switch:~$ nv set interface swp51 neighbor ipv4 10.5.5.51 lladdr 00:00:5E:00:53:51 state permanent
nv set system global arp base-reachable-time
Configures how long a neighbor cache entry is valid. The entry is valid for at least the value between the base reachable time divided by two and three times the base reachable time divided by two. You can specify a value between 30 and 2147483 seconds. The default value is auto; NVUE derives the value for auto from the /etc/sysctl.d/neigh.conf file.
Version History
Introduced in Cumulus Linux 5.6.0
Example
cumulus@switch:~$ nv set system global arp base-reachable-time 50