Igmp-Related Problems - HP ProCurve 6400cl Series Management And Configuration Manual

One or more CDP neighbors appear intermittently or not at all in the
switch's CDP Neighbors table. On a 5300xl switch, this may be caused by
more than 60 neighboring devices sending CDP packets to the switch. (On a
3400cl/6400cl switch with CDP packet-reading enabled, the neighbor limit
matches the number of physical ports on the switch.) Exceeding the neighbor
limit can occur, for example, where multiple neighbors are connected to the
switch through non-CDP devices such as many hubs.
The Same CDP Switch or Router Appears on More Than One Port in
the CDP Neighbors Table. This can occur in instances where:
A connected device is the STP root.
■
The STP root device is transmitting CDP packets outbound over all links,
■
including redundant links that STP may be blocking in non-root devices.
In this case, a non-root device reading the CDP packets it receives can show
an entry in its CDP Neighbors table for every port on which it receives a CDP
packet from the root device.

IGMP-Related Problems

IP Multicast (IGMP) Traffic That Is Directed By IGMP Does Not Reach
IGMP Hosts or a Multicast Router Connected to a Port. IGMP must
be enabled on the switch and the affected port must be configured for "Auto"
or "Forward" operation.
IP Multicast Traffic Floods Out All Ports; IGMP Does Not Appear To
Filter Traffic. The IGMP feature does not operate if the switch or VLAN does
not have an IP address configured manually or obtained through DHCP/Bootp.
To verify whether an IP address is configured for the switch or VLAN, do either
of the following:
Try Using the Web Browser Interface: If you can access the web
■
browser interface, then an IP address is configured.
■ Try To Telnet to the Switch Console: If you can Telnet to the switch,
then an IP address is configured.
■ Using the Switch Console Interface: From the Main Menu, check the
Management Address Information screen by clicking on
1. Status and Counters
2. Switch Management Address Information
Troubleshooting
Unusual Network Activity
C-13