User manual

Release Notes for Catalyst 6500 Series Content Switching Module Software Release 2.2(8)

78-12569-16

Limitations and Restrictions

• When receiving out-of-order UDP fragments, the CSM will bridge the packets to the appropriate

peer VLAN in the bridging-mode.

• There is an enhancement to the predictor IP hash and cookie hash. The CSM will perform a

secondary hash if the first hash value resolves in mapping to an out-of-service real server. This

allows even distribution of connections. Previously, when a real server became out-of-service, all of

its intended connections would go to the next real server in sequence.

Limitations and Restrictions

• The CSM does not support pipelines (multiple HTTP requests sharing the packet boundary) with the

persistent rebalance feature.

• When configuring Route Health Injection (RHI), proxy ARP must be disabled on the Catalyst 6500

Series chassis (proxy-ARP is enabled by default). You must disable proxy ARP on a per-interface

basis in the interface submode. We recommend that you disable proxy ARP on the VLAN level using

the no ip proxy arp command.

• The meaning of having no minimum connections (MINCONNS) parameter set in the real submode

is different between release 2.2(1) and later releases.

Note Having the no MINCONNS parameter set is the default behavior.

In all releases, when the MINCONNS value is set, once a real server has reached the maximum

connections (MAXCONNS) state, no additional session is balanced to it until the number of open

sessions to that real server falls below MINCONNS. With the no MINCONNS value set in release

1.1(1), no additional session would be balanced until the number of open sessions to that real server

falls to 0.

• Slot 1 is reserved for the supervisor engine. Slot 2 can contain an additional redundant supervisor

engine in case the supervisor engine in slot 1 fails. If a redundant supervisor engine is not required,

you can insert the CSM in slots 2 through 6 on a 6-slot chassis, slots 2 through 9 on a 9-slot chassis,

or slots 2 through 13 on a 13-slot chassis.

• The connection redundancy feature in 2.1(1) only backs up TCP connections from active to standby

CSM. There is no support for connection redundancy of UDP and other non-TCP protocols.

• There is no support for client NAT of IP protocols other than TCP or UDP.

• If neither a real server nor a corresponding virtual server has an explicitly configured TCP/UDP

port, then probes requiring such a port are not activated. All CSM health probes other than ICMP

periodically create connections to specific TCP or UDP ports on configured real servers. If a health

probe is configured on a real server without a configured TCP or UDP port, the CSM chooses the

TCP or UDP port to probe from the virtual servers with which the real server is associated. If neither

the real server nor the virtual server has a configured port, the CSM simply ignores any configured

probes requiring ports to that real server.