System Forwarding
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 system forwarding ecmp-hash destination-ip
Turns ECMP hashing on the destination IP field on or off. The default setting is off
.
Custom hashing lets you specify what to include in the hash calculation during load balancing between multiple next hops of a layer 3 route (ECMP hashing).
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash destination-ip on
nv set system forwarding ecmp-hash destination-port
Turns ECMP hashing on the destination port field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash destination-port on
nv set system forwarding ecmp-hash gtp-teid
Turns ECMP hashing on the GTP TEID field on or off. The default setting is off
.
GTP TEID-based ECMP hashing is only applicable if the outer header egressing the port is GTP encapsulated and if the ingress packet is either a GTP-U packet or a VXLAN encapsulated GTP-U packet.
- Cumulus Linux supports GTP Hashing on NVIDIA Spectrum-2 and later.
- GTP-C packets are not part of GTP hashing.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash gtp-teid on
nv set system forwarding ecmp-hash ingress-interface
Turns ECMP hashing on the ingress interface on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash ingress-interface on
nv set system forwarding ecmp-hash inner-destination-ip
Turns ECMP hashing on the inner destination IP address field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash inner-destination-ip on
nv set system forwarding ecmp-hash inner-destination-port
Turns ECMP hashing on the inner destination port field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash inner-destination-port on
nv set system forwarding ecmp-hash inner-ip-protocol
Turns ECMP hashing on the inner IP protocol field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash inner-ip-protocol on
nv set system forwarding ecmp-hash inner-ipv6-label
Turns ECMP hashing on the inner IPv6 label field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash inner-ipv6-label on
nv set system forwarding ecmp-hash inner-source-ip
Turns ECMP hashing on the inner source IP address field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash inner-ip-protocol on
nv set system forwarding ecmp-hash inner-source-port
Turns ECMP hashing on the inner source port field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash inner-source-port on
nv set system forwarding ecmp-hash ipv6-label
Turns ECMP hashing on the IPv6 label field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash ipv6-label on
nv set system forwarding ecmp-hash ip-protocol
Turns ECMP hashing on the IP protocol field on or off. For IP traffic, the switch uses IP header source and destination fields in the hash calculation. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash ip-protocol on
nv set system forwarding ecmp-hash source-ip
Turns ECMP hashing on the source IP field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash source-ip on
nv set system forwarding ecmp-hash source-port
Turns ECMP hashing on the source port field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-hash source-port on
nv set system forwarding ecmp-weight-normalisation max-hw-weight
Configures the maximum number of hardware entries for weighted ECMP. You can specify a value between 8 and 4096. The default value is 32.
The NVIDIA Spectrum switch supports weight programming for ECMP by repeating each individual path, which consumes resources. To reduce hardware utilization of ECMP resources, you can enable weight normalization.
In Cumulus Linux 5.9 and earlier, the minimum number of hardware entries for weighted ECMP that you can specify is 10 and the maximum number is 255.
Version History
Introduced in Cumulus Linux 5.7.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-weight-normalisation max-hw-weight 100
nv set system forwarding ecmp-weight-normalisation mode
Enables (enabled
) and disables (disabled
) ECMP weight normalization.
The NVIDIA Spectrum switch supports weight programming for ECMP by repeating each individual path, which consumes resources. To reduce hardware utilization of ECMP resources, you can enable weight normalization.
Version History
Introduced in Cumulus Linux 5.7.0
Example
cumulus@switch:~$ nv set system forwarding ecmp-weight-normalisation mode enabled on
nv set system forwarding hash-seed
Configures a unique hash seed for each switch to prevent hash polarization, a type of network congestion that occurs when multiple data flows try to reach a switch using the same switch ports.
You can set a hash seed value between 0 and 4294967295. If you do not specify a value, switchd
creates a randomly generated seed.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding hash-seed 50
nv set system forwarding host-route-preference
Configures the forwarding host route preference: route
, neighbour
, or route-and-neighbour
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding host-route-preference neighbour
nv set system forwarding lag-hash
Configures custom hashing to load balance between multiple interfaces that are members of the same bond.
The switch distributes egress traffic through a bond to a slave based on a packet hash calculation, providing load balancing over the slaves; the switch distributes conversation flows over all available slaves to load balance the total traffic. Traffic for a single conversation flow always hashes to the same slave. In a failover event, the switch adjusts the hash calculation to steer traffic over available slaves.
nv set system forwarding lag-hash destination-ip
Turns lag hashing on the destination IP address field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding lag-hash destination-ip on
nv set system forwarding lag-hash destination-mac
Turns lag hashing on the destination MAC address field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding lag-hash destination-mac on
nv set system forwarding lag-hash destination-port
Turns lag hashing on the destination port field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding lag-hash destination-port on
nv set system forwarding lag-hash ether-type
Turns lag hashing on the ether type field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding lag-hash ether-type on
nv set system forwarding lag-hash gtp-teid
Turns lag hashing on the GTP TEID field on or off. GTP carries mobile data within the core of the mobile operator’s network. Traffic in the 5G Mobility core cluster, from cell sites to compute nodes, have the same source and destination IP address. The only way to identify individual flows is with the GTP TEID. Enabling GTP hashing adds the TEID as a hash parameter and helps the Cumulus Linux switches in the network to distribute mobile data traffic evenly across ECMP routes.
The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding lag-hash gtp-teid on
nv set system forwarding lag-hash ip-protocol
Turns lag hashing on the IP protocol field on or off. For IP traffic, the switch uses IP header source and destination fields in the hash calculation. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding lag-hash ip-protocol on
nv set system forwarding lag-hash source-ip
Turns lag hashing on the source IP address field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding lag-hash source-ip on
nv set system forwarding lag-hash source-mac
Turns lag hashing on the source MAC address field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding lag-hash source-mac on
nv set system forwarding lag-hash source-port
Turns lag hashing on the source port field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding lag-hash source-port on
nv set system forwarding lag-hash vlan
Turns lag hashing on the VLAN ID field on or off. The default setting is off
.
Version History
Introduced in Cumulus Linux 5.2.0
Example
cumulus@switch:~$ nv set system forwarding lag-hash vlan on
nv set system forwarding profile
Configures the forwarding resource profile: default
, l2-heavy
, l2-heavy-1
, l2-heavy-3
, v4-lpm-heavy
, v4-lpm-heavy-1
, v6-lpm-heavy
, v6-lpm-heavy-1
, ipmc-heavy
, ipmc-max
, or lpm-balanced
.
Version History
Introduced in Cumulus Linux 5.4.0
Example
cumulus@switch:~$ nv set system forwarding profile l2-heavy
nv set system forwarding programming
Configures forwarding programming logging.
nv set system forwarding programming log-level
Configures the forwarding programming log level: debug
, info
, critical
, warning
, or error
. The default log level is info
.
Version History
Introduced in Cumulus Linux 5.0.0
Example
cumulus@switch:~$ nv set system forwarding programming log-level error