tunnel-mtu (Services IPsec VPN)
Syntax
tunnel-mtu bytes;
Description
Maximum transmission unit (MTU) size for IPsec tunnels. This defines the maximum size of an IP packet, including the IPsec overhead.
Options
bytes—MTU
size.
Default: 1500 bytes
Range: 256 through 9192 bytes
Clear the IPsec SA in tunnel-mtu to accommodate Jumbo frames larger than 1500 bytes.
Validation checks have been introduced to restrict the configuration of tunnel MTU for HA link encryption tunnels in a Multinode High Availability setup. This check ensures that the end-to-end MTU for HA links using IPv6 encryption meets the minimum requirement of 2000 bytes.
For example, if your configuration includes the following stanza, and MTU is less than 2000 bytes, you'll receive a commit check error:
user@host# set security ipsec vpn L3HA_IPSEC_VPN tunnel-mtu <bytes>
Validation restricts tunnel MTU configuration to ensure HA links with IPv6 encryption meet the minimum 2000-byte MTU requirement for reliable high availability operations.
Required Privilege Level
interface—To view this statement in the configuration.
interface-control—To add this statement to the configuration.
Release Information
Statement introduced in Junos OS Release 7.5.