Configures the MTU for IPv4/IPv6 L2GRE tunnel endpoints

The MTU is the largest physical packet size (in bytes) transmittable within the tunnel. Any messages larger than the configured MTU are divided into smaller packets before transmission. Larger the MTU greater is the efficiency because each packet carries more user data, while protocol overheads, such as headers or underlying per-packet delays remain fixed; the resulting higher efficiency means a slight improvement in bulk protocol throughput. A larger MTU results in the processing of fewer packets for the same amount of data.

Supported in the following platforms:

  • Access Points — AP505i, AP510i/e, AP560i/h
  • Service Platforms — NX5500, NX7500, NX7510, NX7520, NX7530, NX9500, NX9510, NX9600, VX9000


mtu [ipv4 <900-1476>|ipv6 <1236-1456>]


mtu [ipv4 <900-1476>|ipv6 <1236-1456>]
mtu [ipv4 <900-1476>| ipv6 <1236-1456>] Configures the MTU for L2GRE tunnel endpoints
  • ipv4 <900-1476> – Configures IPv4 L2GRE tunnel endpoint MTU from 900 - 1476. The default is 1476.
  • ipv6 <1236-1456> – Configures IPv6 L2GRE tunnel endpoint MTU from 1236 - 1456. The default is 1456.


nx9500-6C8809(config-profile testNX9500-gre-tunnel-testGREtunnel)#mtu ipv4 1200

nx9500-6C8809(config-profile testNX9500-gre-tunnel-testGREtunnel)#mtu ipv6 1300

nx9500-6C8809(config-profile testNX9500-gre-tunnel-testGREtunnel)#show context
 gre tunnel testGREtunnel
  mtu ipv4 1200
  mtu ipv6 1300
  establishment-criteria rf-domain-manager
nx9500-6C8809(config-profile testNX9500-gre-tunnel-testGREtunnel)#