Technical data

SMLT network design considerations 31
Release Notes for the Passport 8600 Release 3.7.6
• Use the following procedure when designing an SMLT network. For more
information, refer to Network Design Guidelines (313197-D
).
1 To ensure proper IST connectivity, define a separate VLAN for the IST
protocol:
config mlt 1 ist create ip <value> vlan-id <value>
Note: Do not enable a routing protocol on this VLAN.
2 To ensure that IST is not disabled inadvertently, disable CP-limit on the
IST ports:
config ethernet <slot|port> cp-limit disable
3 Keep CP-limit enabled on the SMLT ports and change multicast-limit
value to 6000:
config ethernet <slot|port> cp-limit enable
multicast-limit 6000
Note: Nortel Networks recommends that you keep CP limit enabled on
SMLT ports to protect the SMLT aggregation switches against
unforeseen DOS attacks.
4 Disable loop detect on SMLT ports:
config ethernet <slot|port> loop-detect disable
Note: For Release 3.7.6, Nortel Networks recommends that you disable
loop detect; this recommendation is in direct contrast to that made for
earlier releases.
5 Enable tagging on SMLT links:
config ethernet <slot|port> perform-tagging enable
Note: Nortel Networks recommends that you enable tagging on SMLT
ports and drop untagged frames to ensure that SMLT client switches with
default configurations do not adversely affect SMLT aggregation switch
behavior.
6 Enable drop untagged frames on SMLT links:
config ethernet <slot|port> untagged-frames-discard
enable