User manual

40
Release Notes for Catalyst 6500 Series Content Switching Module Software Release 2.2(8)
78-12569-16
Caveats
This error is returned by a router that receives a packet too large for it to forward when the DF bit
is set.
Note This error is sent only if the DF bit is set; otherwise, packets are just fragmented and passed
through.
The packet is dropped and the ICMP error is sent back to the host where the packet originated. This
action tells the originating host that it needs to reduce the size of its packets before they can be
routed.
Recent system implementations also include the MTU of the next hop in the ICMP message so that
the source knows how big its packets can be.
Workaround: Disable the path MTU discovery on the servers behind the CSM.
• CSCdx51869
When an active CSM receives an ARP request on one VLAN in a bridged VLAN pair, it should
transmit that ARP frame onto the other VLAN in the pair. If the ARP request is for an IP address
outside the subnet for which the CSM is configured, the CSM drops the ARP request. This situation
may cause a problem when proxy ARP is employed across the two bridged VLANs. The CSM then
may drop any proxy ARP request for an IP address not in its directly connected subnet. This severely
limits the IP addresses to which hosts employing proxy ARP are able to communicate.
This issue exists in CSM releases 2.1(1), 2.1(2), 2.1(3), 2.2(1), and 2.2(2a). It does not exist in any
1.x release.
Workaround: Avoid using proxy ARP through bridged VLANs on the CSM.
• CSCdx62207
With certain patterns of FTP traffic passing through a CSM virtual server on which service ftp is
enabled, there is some possibility that the CSM will fail. This issue exists in CSM releases 1.x,
2.1(1), 2.1(2), 2.1(3), 2.2(1), and 2.2(2a).
Workaround: Disable service ftp on all virtual servers.
• CSCdx66661
When the active CSM in a redundant pair is reset and the fault tolerance preempt option is enabled,
it is possible for some traffic to be misdirected toward the standby CSM. This condition will persist
until the standby CSM is reset. This issue exists in CSM releases 1.x, 2.1(1), 2.1(2), 2.1(3), 2.2(1),
and 2.2(2a).
Workaround: Reset the standby CSM or do not employ the fault tolerance preempt option.
Note If the standby CSM is reset, application traffic will be handled by the active CSM and not
experience disruption.
• CSCdx66674
When the CSM receives a UDP frame with a 0 checksum on which a NAT operation is to be
performed, the CSM will erroneously overwrite the checksum, causing a UDP frame with an
incorrect checksum to be transmitted. This issue exists in CSM releases 2.1(1), 2.1(2), 2.1(3), 2.2(1),
and 2.2(2a).
Workaround: None.