Avaya ESS User Manual page 50

ESS Overview
Figure 18: ATM - single ESS server first takeover scenario
PN #1
PN #2 does not have
an IPSI but remains in
service via PN #3
In the second takeover example (see
Communication between the Main server and Port Networks 1 through 3 has not been affected
by the outage. The IPSIs in Port Network 4 and Port Network 5 can no longer communicate with
the Main server. The no service timer activates. When the no service timer expires the IPSIs in
Port Networks 4 and 5 request service from the S8500 ESS server.
50 Avaya Enterprise Survivable Servers (ESS) Users Guide
S8710 Media Server
(Main Server)
disc COMPACT
disc COMPACT
PN #2
PN #3
Port Network Control Link (EAL)
IP Connection into Control Network
Server or Network Failure
VoIP Path
DSIC LInk
cycmatm2 KLC 031605
Figure
1
2
UID
S8500 ESS Server
(1st Alternative)
1
2
UID
disc
PN #4
ATM
CSS / EI (Fiber)
ATM / ATM-EI (Fiber)
Dup Link
Out of Service
19), the customer experiences a network failure.
PN #6
PN #5
PN #5 does not have
an IPSI but remains in
service via PN #4