Standard Local Survivability (SLS) – Everything You Always

Wanted to Know

RMAUG Professional Development Series 11/17/2010

Dwight Reifsnyder

2

“If you have an apple and I have an apple and we exchange apples then you and I will still each have one apple. But if you have an idea and I have an idea and we exchange these ideas, then each of us will have two ideas.”

George Bernard Shaw

Boulder Valley School District

SLS – EYAWTK Overview

Avaya Survivability Options SLS Features BVSD Application Programming Tips/Tricks Real world results

ESS – Enterprise Survivable Server◦ ESS allows media servers to be used as alternate controllers within a system by leveraging IP

control of port network gateways and can be completely independent of the main servers both functionally and geographically. ESS protects the communication system against a catastrophic main server failure and, at the same time, provides service to port network gateways that have been fragmented away from their current controlling entity. (Original white paper definition from my hero, Greg Weber

LSP – Local Survivable Processor◦ Avaya offers the Local Survivable Processor to continue to provide service in the case of broken

connectivity between remote sites and main locations. In addition, Avaya empowers the administrator with the ability to define how the system behaves in the case of lost network connectivity. CM Featureset is still 3.0?, this is way is now AKA Enhanced Local Survivability

SLS – Standard Local Survivability◦ SLS is a configurable software module that enables a local Media Gateway to provide a core set

of MGC functions when no link is available to the CM server, a Local Survivable Processor (LSP), or an Enterprise Survivable Server (ESS).

Avaya Survivability Options (3.1)

New Definitions…

◦ SCS - Survivable Core Server (ESS)

◦ SRS – Survivable Remote Server (LSP)

Avaya Survivability Options (6.0)

Survivable Remote Processor (SRP): In an SRP option, DEFINITY server SI provided continued service for a single fiber-Port Network Connected Center Stage Switch (fiber-PNC CSS) port network.

ATM WAN Spare Processor (WSP): In a WSP option, multiple DEFINITY server R processor port networks provided continued service for systems with ATM port network connectivity

Avaya Survivability Options (1.0)

In engineering, redundancy is the duplication of critical components of a system with the intention of increasing reliability of the system, usually in the case of a backup or fail-safe.

In computer networking resilience is the ability to provide and maintain an acceptable level of service in the face of faults and challenges to normal operation.

Resilient vs. Redundant

Call capability for analog, DCP, and IP phones ISDN BRI/PRI trunk interfaces Non-ISDN digital DS1 trunk interfaces Outbound dialing through the local PSTN (local trunk gateway) from

analog, DCP, and IP phones Inbound calls from each trunk to pre-configured local analog or IP phones

that have registered Direct inward dialing Multiple call appearances Hold and call transfer functions Contact closure feature Local call progress tones (dial tone, busy, etc.) Emergency Transfer Relay (ETR) in cases of power loss Auto fallback to primary MGC IP station registration

SLS Features (what it does)

Many small business customers employ custom calling features such as call waiting, from the BOC/LEC, attempting a more PBX-like capability. These features are not supported by SLS.

Calling party name/number information to digital station displays Caller ID on outgoing analog station calls Caller ID on incoming analog loop-start trunk calls Three party conferences Last Number Redial Call Forwarding-Busy/Don’t Answer No Music On Hold source or announcement playback Call Center features, including ASAI Connection Preserving Failover/Failback for H.248 Gateways

SLS Limitations (what it doesn’t)

SLS is not a replacement for ESS or LSP survivability, which offer full call-feature functionality and full translations in the survivable mode. Instead, SLS is a cost-effective survivability alternative offering limited call processing in survivable mode.

SLS is Not CM!

Product G250 G350 G430 G450

Target Market Very Small RBO (2-14

seats)

Small RBO(8-72 seats)

Medium/large RBO (>40

seats)

Medium/large RBO (>40

seats)

Endpoint support

Model dependant

Analog, DCP, PoE, BRI

Analog, DCP, BRI

Analog, DCP, BRI

PSTN Trunk options

Model dependant

FXO, BRI, T1/E1

FXO, BRI, T1/E1

FXO, BRI, T1/E1

Survivability options

Dual WAN, Dialup

backup, SLS, LSP

Dual WAN, Dialup

backup, SLS LSP

Dual WAN, Dialup

backup, SLS, LSP

Dual WAN, Dialup

backup, SLS, LSP

SLS IP Endpoints

70 70 150 240

Media Gateways Supporting SLS

Analog – 2500

DCP – 2402, 2410, 2420, 6402, 6402D, 6408, 6408+, 6408D, 6408D+, 6416D+, 6424D+, 8403B, 8405B, 8405B+, 8405D, 8405D+, 8410B, 8410D, 8411B, 8411D, 8434D

IP - 4601, 4602, 4602sw, 4610sw, 4612, 4620, 4620sw, 4621, 4622, 4624, 4625, 1603*, 1608*, 1616*, 9610*, 9620*, 9630*, 9640*, 9650*

* map to similar 46xx handset

Handsets Supported

In contrast to the server-based survivability features, SLS operates entirely from the media gateway and requires a data set comprised of Avaya Aura Communication Manager translations (survivable ARS analysis and configuration data).

SLS Operates at the Gateway

This data set is compiled and distributed to a group of devices using the Provisioning and Installation Manager (PIM). In the absence of the PIM, the data set can be configured manually from individual media gateways using CLI commands.

SLS Configuration Data

change node-names ip

CM Config – Add Gateways

change system-parameters mg-recovery-rule 1

CM Config – Set Recovery Rule

change media-gateway 8

CM Config – Media Gateways

Change station

CM Config – Stations

sls station 5781 ip set cor unrestricted set password xx set type ip4620 exit

Gateway Config - Station

sls trunk-group 1 loop-start set dial dtmf set tac 121 add port v101 exitset fac ars1 9exit

Gateway Config – 911 trunk

dial-pattern 911 set max 3 set min 3 set tgnum 1 set type emergency set deny n exit

sls set max-ip-registrations 240 set slot-config v1 mm711exitset sls enable

Gateway Config – Enable SLS

set mgc list 10.0.50.10,10.6.18.5

set reset-times primary-search 1

set reset-times total-search 2set reset-times transition-point

1

MGC list and Timers!

Gateway MGC List & Recovery

0:00 8730 Primary becomes unavailable (simulate by disabling network ports)

Phones start h323 link timer, value 1 minute

Gateway’s start off h248 link timer, value 1 minute (+20 seconds)

8510 LSP is patiently waiting for an MGC to contact it, will not accept phone registrations until first gateway registers

1:00 Phones begin scrolling through gatekeeper list, none will be available

1:20 Gateways begin to attempt registration to LSP

~1:30 Upon gateway registration LSP becomes active, begins to accept phones

Phones continue registration to LSP until all are registered, end of sequence. Manual return to 8730 when it is available.

2:40 If LSP is not available, Gateways initiate SLS mode at this time

~3:10 Gateways are ready in SLS mode and begin accepting phone registrations

Phones continue to register to SLS until all are registered.

Gateway continues to search for available 8730 or 8510. If 8730 or 8510 becomes available, gateway begins recovery timer, after 3 minutes re-registers to 8730. Gateway exits SLS mode, phones reboot

5:00 Total search time is reached, if gateways were not programmed for SLS mode they would reboot at this time. With SLS enabled they should not reach this parameter.

12:00 if phones have not yet registered with any gatekeeper, they reboot, get LLDP values and begin to search for a gatekeeper again.

BVSD Failover Timeline

By using existing POTs line, no additional costs are incurred

Because we use defined extension ranges SLS configuration is simple and static

LSP provides redundancy, SLS provides a third level of resilience

Reliability of 911 (life safety) services are enhanced with no additional costs

Summary – BVSD SLS Config