ATM Release Notes

ATM Release Note for HP-UX 11i v2
Known Problems and Workarounds
Chapter 1 9
• During system startup, an ELAN interface’s initialization might not complete before the
IP initialization stars. This can lead to errors if the IP configuration uses that ELAN
interface. An example of this is when static routes use the ELAN interface.
Workaround: To avoid this, a tunable delay parameter (ATM_ELAN_TIMEOUT) has been
added to the ATM subsystem file (/etc/rc.config.d/atmconf). This parameter specifies
how long the ATM startup script waits for the ELAN interface initializations to complete.
Note that the default value for the ATM_ELAN_TIMEOUT parameter is 0 (zero), which means
“no delay.”
• You might have to specify the LAN type during ELAN interface configuration, if you are
in either of these situations:
— You have an ELAN connectivity problem, and your ATM switch’s manufacturer
diagnoses the problem as being caused by the absence of the LAN type during
configuration.
— Your ATM switch provides the capability of specifying the LAN type during
configuration, and you have configured the LAN Emulation services to require the
LAN type during configuration.
Workaround: The only way you can do this is to manually specify the LAN type (the
parameter is called lan_type) in the ELAN interface’s configuration file; you cannot do
this within SAM. Set the parameter HP_ATM_ELAN_TYPE as follows:
HP_ATM_ELAN_TYPE = 802.3 for Ethernet
HP_ATM_ELAN_TYPE = 802.5 for Token Ring
However, keep in mind that each time you use SAM to modify the interface’s
configuration, SAM overwrites the ELAN interface configuration file. So, for example,
you’ve manually specified the LAN type in an ELAN interface’s configuration file. Then,
you later use SAM to modify some other part of the interface’s configuration. When you
save the configuration in SAM, the previous configuration file (with the LAN type you
manually specified) is overwritten. This means you then must manually re-edit the
configuration file to re-specify the LAN type.
• At this time, HP’s implementation of Multiprotocol Over ATM (MPOA) supports putting
the MPS on only a FORE router.
• In MPOA, if a shortcut route consists of MPCs that are on HP systems and an MPS that is
on a Cisco router, when you try to send traffic over that shortcut, no data will be
transferred over the shortcut. This might cause the applications to hang. If you issue the
command atmmgr card_instance_number show on the MPCs, you will see that a
shortcut VCC is established between the MPCs. However, the traffic will not be able to
travel over the shortcut VCC.