Transport Optional Upgrade Release (TOUR) 2.5 Release Notes

Known Problems and Limitations

This section includes information on known problems and limitations in TOUR 2.5 and its

components.

Known Problem and Workaround

This section lists the known problem in TOUR 2.5 and also the recommended workaround.

Problem

TCP/IPv6 connections that use HP-UX IPSec may have temporary drops in throughput and

intermittent connection timeouts. This problem occurs when multiple TCP/IPv6 connections

using HP-UX IPSec have simultaneous first-time sends of oversize packets, which are larger

than the maximum segment size (MSS).

Workaround To solve this problem, complete the following:

• Use the following ndd command to disable the sending limit for ICMPv6 error messages:

ndd -set /dev/ip6 ip6_icmp_interval 0

This command sets the ndd ip6_icmp_interval parameter to 0.

• Add the following entries to the /etc/rc.config.d/nddconf file:

TRANSPORT_NAME[<index>]=ip6

NDD_NAME[<index>]=ip6_icmp_interval

NDD_VALUE[<index>]=0

where, the value of index is an integer from 0 to 99.

By convention, the first set of entries for an ndd parameter uses an index value of 0, the

second set of entries’ parameter uses an index value of 1, and so on.

Limitations

The following limitations exist for TOUR 2.5 components on the HP-UX 11i v1 operating

system.

IPv6 Transport Limitations

The limitations of IPv6 included in HP-UX 11i v1 TOUR 2.5 are as follows:

• Multihomed Host Limitation