Demand test descriptions and error codes - Avaya Support

Executing a PKT-INT Interchange
There are two ways to interchange PKT-INTs, spontaneous and planned.
● A spontaneous interchange is usually caused by a fault, and:
- Stable calls are retained
- LAPD links are restarted
- Some data may be lost
● A planned interchange can be requested by Services’ personnel or by software for
maintenance or periodic testing.
- LAPD links are migrated from the active to the standby PKT-INT
- No data is lost during the interchange
The active server’s PCD has socket connections to both active and standby IPSIs. server
interchange and IPSI interchange are independent of each other. IPSIs in a PN can be
interchanged independently of IPSIs in other PNs.
Spontaneous PKT-INT Interchange
The standby PKT-INT is not kept up-to-date with the links terminated by the active PKT-INT.
During a spontaneous interchange of PKT-INTs, the standby PKT-INT is refreshed with the link
information by the active PCD and the standby PKT-INT is activated with a warm reset. A
spontaneous interchange of PKT-INTs may result in loss of some up-stream and down-stream
data.
● PCD maintains socket connections to the active and the standby PKT-INTs, via the SIM.
● server sends control and data packets only to the active PKT-INT.
● Standby PKT-INT has no information about the LAPD links.
● On a spontaneous interchange, the standby PKT-INT is “refreshed” by the PCD. That
means the LAT and the LCT are sent to the PKT-INT, and the standby PKT-INT is made
active by a warm interrupt.
Planned PKT-INT Interchange (Link Migration)
A planned interchange of PKT-INTs uses link migration to assure that no data is lost during the
interchange. On a planned interchange of PKT-INTs, software initiates the link migration by
sending commands to the active and standby PKT-INTs to make a peer link between the
PKT-INTs and to start the link migration process. Down-stream and up-stream messages can
be processed by the PKT-INTs during the link migration process. As long as the PKT-INT
interchange has not been completed, PCD should continue to send down-stream messages to
the active PKT-INT. If a down-stream data packet is for a link that has not yet been migrated
over to the standby PKT-INT, the active PKT-INT processes it and sends it out.
726 Maintenance Alarms for Communication Manager, Media Gateways and Servers