Avaya CMC1, Maintenance Procedures

Page: 133 / 426

Server initialization, recovery, and resets
Link Recovery
Maintenance Procedures 133
December 2003
Table 47: General Link Recovery process
Process
sequence
Description
1. Link failure detected (see Conditions that trigger Link Recovery on page 131)
2. The Primary and Total Search Timers begin running. The gateway attempts to re-
establish the H.248 link with original server, which is the first element in the Media
Gateway Controller (MGC) list.
See Administering the MGC list on page 137 for instructions on administering this
list.
See Administering the gateway timers and Transition Point on page 136 for
instructions on administering the Primary and Total Search Timers.
3. If the gateway cannot reconnect with the original server, then it searches the MGC
list (in order) for alternate resources (list elements 2-4) that are above the Transition
Point (if set). These alternate resources can be:
S8300 : 1-3 S8300s configured as Local Spare Processors (LSPs)
S8500 and S8700 : 1-3 C-LAN circuit packs within the primary server’s
configuration
The Total Search Timer continues running.
See Administering the MGC list on page 137 for instructions on administering this
list and on setting the Transition Point.
4. If the Primary Search Timer expires before the gateway can re-establish the link to
the alternate resources that are above the Transition Point in the MGC list, then the
gateway crosses the Transition Point and begins searching the other resources in the
list. The gateway makes only one connection attempt with any resources below the
Transition Point.
5. If the gateway cannot re-establish the link to any of the resources below the
Transition Point, then it starts over at the top of the MGC list and continues to the
end, making only 1 reconnection attempt to each element in the list. This continues
until the Total Search Timer expires.
6. If the gateway still cannot connect to any alternate resources and Total Search Timer
expires, the software raises a warning alarm. See
Maintenance during recovery on
page 134 for more information about the server and gateway alarm notification
strategies.
The server’s Link Loss Delay Timer should be the last timer to expire, meaning that
the server holds its call control information until all other means of re-establishing
the have been exhausted.
Note: If the Link Loss Delay Timer expires but the gateway successfully connects
with an alternate resource, the system generates a warning alarm anyway, even
though the H.248 link is up.