AIS AI2524 Manuel D’Utilisation
AI2524 Router Card User’s Manual
Page 9-54
August 1997
2524UM
Specify the MTU Size
All interfaces have a default maximum packet size. However to reduc
fragmentation, you can set the MTU size of the packets sent on the in-
terface. The minimum value is 512; the default and maximum packet
size depends on the interface type.
fragmentation, you can set the MTU size of the packets sent on the in-
terface. The minimum value is 512; the default and maximum packet
size depends on the interface type.
Changing the MTU value with the
mtu
interface configuration com-
mand can affect the CLNS MTU value. If the CLNS MTU is at its
maximum given the interface MTU, the CLNS MTU will change with
the interface MTU. However, the reverse is not true; changing th
CLNS MTU value has no effect on the value for the
maximum given the interface MTU, the CLNS MTU will change with
the interface MTU. However, the reverse is not true; changing th
CLNS MTU value has no effect on the value for the
mtu
interface con-
figuration command.
In interface configuration mode, set the CLNS MTU packet size for a
specified interface:
specified interface:
clns mtu
size
Warning: The CTR card does not support the switching of frames
larger than 4472 bytes. Interoperability problems might
occur if CTR cards are intermixed with other Token Ring
cards on the same network. These problems can be mini
mized by lowering the CLNS MTU sizes to be the same on
all routers on the network.
occur if CTR cards are intermixed with other Token Ring
cards on the same network. These problems can be mini
mized by lowering the CLNS MTU sizes to be the same on
all routers on the network.
Disable Checksums
When the ISO CLNS routing software originates a CLNS packet, by
default it generates checksums. In interface configuration mode, dis-
able checksum generation:
default it generates checksums. In interface configuration mode, dis-
able checksum generation:
no clns checksum
Warning: Enabling checksum generation has no effect on routing
packets (ES-IS, ISO IGRP, and IS-IS) originated by th
router; it applies to pings and traceroute packets.
router; it applies to pings and traceroute packets.
Disable Fast Switching Through the Cache
Fast switching through the cache is enabled by default for all sup-
ported interfaces. In interface configuration mode, disable fast switch-
ing:
ported interfaces. In interface configuration mode, disable fast switch-
ing:
no clns route-cache
Warning: The cache still exists and is used after the
no clns
route-cache
interface configuration command is
used; the software just does not do fast switching through
the cache.
the cache.