Alcatel-Lucent 7210 SAS M Service Manual page 107

Subscriber Services
If the physical mtu on an egress interface indicates the next hop on an SDP path cannot support the
current path-mtu, the operational path-mtu on that SDP will be modified to a value that can be
transmitted without fragmentation.
The no form of this command removes any path-mtu defined on the SDP and the SDP will use the
system default for the SDP type.
The default path-mtu defined on the system for the type of SDP is used.
Default
7210 SAS M Services Guide Page 107