User`s guide

AT-S60 Version 2.0.0 NE Management Software Release Notes
PN 613-50544-00 Rev B 4 Allied Telesyn, Inc.
STP/RSTP with IGMP Snooping. On the bridge that the router isn't directly connected to, the
router port has to be manually set on both the primary link and secondary link.
Processing of IGMP Packets Slow when Multicasting. The processing of IGMP reports on
the same line card as the router/multicaster is delayed. However, if an IGMP Host on a different
line card than the router/multicaster is learned first, then IGMP hosts on the same line card of
the router/multicaster will be learned quickly.
There are three ways to resolve this issue when using this version of code.
• Configure the multicast server behind a router.
• Ensure that the initial IGMP Host to join is on a card different than the card that the
multicast server.
• Set the management VLAN to a VLAN other than where the IGMP multicasting is being
done. It is recommended that the management VLAN is always separate from regular
network traffic. This will not only alleviate this problem but also make your network more
secure.
Trunking on the AT-8413 Line Card. When Trunking is used to interconnect switches using
the 8413 throughput drops to 60% and flooding occurs when a trunk link goes up/down until
a reboot. It is recommended that the Trunking feature not be configured with the AT-8413
Line Card.
STP and Secondary Links. During STP re-convergence, after the port goes into a Forwarding
State, there may be a throughput loss for 2x the forwarding delay period. We recommend that
the customers default to RSTP because of its backward compatibility and quick
re-convergence. When STP is used and the redundant link resides on a separate blade, this is
not an issue with either an AT-8000 Series or another AT-8400 Series switch is the partner
switch.
Bi-Directional Traffic. When bi-directional traffic is present between a tagged port and an
untagged port, and the tagged port is removed from the VLAN; this tagged port will continue
to have tagged frames on egress for that VLAN until the MAC addresses are aged out or are
cleared for that port. This can be resolved if you either clear the MAC address table, or stop all
bi-directional traffic before deleting the tagged port.