Avaya ESS User Manual page 86

ESS Design and Planning
Table 8: General Link Recovery process (continued)
Process
sequence
3.
4.
5.
6.
Call handling during recovery
While the H.248 link is down, calls already in progress before the link failure remain connected
during the recovery process. Once the link is re-established, normal call processing continues.
If the gateway successfully reconnects, the actual outage is less than 2 seconds. Should the
link failure persist for a few minutes, some features or capabilities are affected:
New calls are not processed.
●
Calls held in queue for an ACD group, attendant group, call park, or calls on hold might be
●
dropped during Link Recovery.
The talk path between two or more points remains up, even if one or all of the parties
●
hangs up.
Music or announcement sources associated with a call remain connected to queued or
●
held calls in progress, even if one or all parties to the call hangs up.
If the link failure continues for several minutes, expect inaccuracies in BCMS, CMS, call
●
attendants, and other time-related statistical reports.
86 Avaya Enterprise Survivable Servers (ESS) Users Guide
Description
If the gateway cannot reconnect with the original server, then it searches the
MGC list (in order) for alternate resources that are above the Transition Point (if
set). These alternate resources can be:
S8300 Media Server: 1-3 S8300s configured as Local Survivable
●
Processors (LSPs).
S8500 and S8700 series media server: 1-3 C-LAN circuit packs within the
●
primary server's configuration.
The Total Search Timer continues running.
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.
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 one reconnection attempt to each element in the list. This
continues until the Total Search Timer expires.
If the gateway still cannot connect to any alternate resources and Total Search
Timer expires, the software raises a warning alarm.
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.
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