ATM Configuration and Troubleshooting Guide

Conﬁguring EMS High Availability over ATM

Conﬁguring EMS HA-ATM for Local Recovery

Chapter 6120

The assigned secondary interface is now ready to take over from the

primary interface if it fails. The HA Related Interface Name ﬁeld in

the “Conﬁgure ATM Card” window now shows all of the assigned

secondary interfaces for each primary ELAN interface.

If the hatmmon daemon is running and the primary ELAN interface fails,

the secondary interface takes over, using the same IP address and

conﬁguration as the primary interface.

Note that SAM might ask if you want to reboot the system. This is

because SAM found a secondary ELAN interface that has an IP address.

This can happen in two situations:

• At some earlier time, EMS HA-ATM was conﬁgured (in SAM) for the

ELAN interface, and a failure occurred. The primary IP address was

successfully transferred from the original primary ELAN interface to

a secondary ELAN interface. So, SAM noticed the change and wants

to know if you want toreboot the system. This is because SAM thinks

the primary IP address is not valid on the interface and wants to

remove the address (SAM considers the interface to still be a

secondary one, and so it cannot have a primary IP address). In this

case, do not reboot the system. This is because the failover

mechanism worked correctly, and the IP address is valid for the

interface, and you want applications to continue using the interface.

• At one time, a secondary ELAN interface was conﬁgured with a

primary IP address. But, the primary IP address is no longer valid

for that interface. So, you need to reboot the system so that the IP

address can be completely removed from the interface.

Step 9. If you are using EMS HA-ATM on HP-UX 10.20, go to one of these two

sections:

• “Conﬁguring the Local Recovery Delay Period” on page 123, if you

need to conﬁgure a delay period for local recovery.

• “Starting the Monitor for the ELAN Interface Resource” on page 124,

if you do not need to conﬁgure a delay period for local recovery.

If you are using EMS HA-ATM on HP-UX 11.X go to the next section,

“Special Considerations for HP-UX 11.X”.