ATM Configuration and Troubleshooting Guide

Configuring EMS High Availability over ATM
Configuring EMS HA-ATM for Local Recovery
Chapter 6116
• Install several secondary ATM adapters, and configure the secondary
ELAN interfaces for a primary ELAN interface “in series.” An
example of this—with one secondary ELAN interface configured on
each secondary adapter—is shown in Figure 6-6 below (note that this
example uses HP-UX 10.20 naming conventions):
Figure 6-6 Secondary ELAN Interfaces Configured “In Series”—Example 1
Note that the order in which the secondary interfaces were
configured determines the order in which they are tried for transfer
during local recovery. In this example, the secondary ELAN
interfaces for primary interface ela0 were configured in this order:
elb0, elc0, and eld0. So, if the primary ELAN interface ela0 fails,
an attempt is made to transfer to the secondary ELAN interface
elb0. If that is not possible, secondary interface elc0 is tried. And, if
that is not possible, secondary interface eld0 is tried. If transfer to
the last secondary interface in the chain—eld0, in this example—is
not possible, the primary ELAN interface is tried again.
Primary
ela0
ELAN I/F
Secondary
elb0
ELAN I/F
Secondary
elc0
ELAN I/F
Secondary
eld0
ELAN I/F
atm1
Adapter
atm2
Adapter
atm0
Adapter
atm3
Adapter
1
2
3
4