Avaya P333R-LB, Руководство по установке и настройке, Страница: 136 / 218

Chapter 13 Layer 3 Redundancy
122 Avaya P333R-LB User’s Guide
Additional Redundancy Schemes
Besides VRRP and SRRP, the P333R-LB implements two additional redundancy
schemes:
•
Real Server Group Backup.
• Real Server Backup.
Real Server Group Backup
You can configure a Real Server Group (RSG) to serve as a backup for a primary
RSG implementing a Virtual Service. You can configure an RSG to backup one or
more primary RSGs.
An RSG can backup a primary RSG, but not a backup RSG. In addition, you cannot
have two RSGs backing up each other.
A backup RSG can run a different Virtual Service than the primary RSG while
supplying backup to all services of the primary RSG.
The backup RSG is not used for the primary RSG’s services until all the Real Servers
in the primary RSG are down. When backup is implemented, the backup RSG runs
the primary RSG’s service in addition to its own services.
When the primary RSG has recovered, it resumes operation. Ongoing sessions
continue going to the backup RSG until they are completed. In addition, in order to
maintain persistency, new sessions might open to the backup RSG.
RSG Backup Configuration Example
The following figure illustrates an RSG Backup configuration.
Figure 13.4 RSG Backup Configuration Example
193.170.1.1
WAN
Edge Router P333R-LB
VIP=193.170.1.3
193.170.1.2
10.1.1.10
RSG
server-group
Real Server 1
10.1.1.1
Real Server 2
10.1.1.2
Real Server 3
10.1.1.3
Server
Server
Server
Real Server 4
10.5.1.3
Real Server 5
10.5.1.4
Real Server 6
10.5.1.5
Server Server
Server
Backup RSG
10.5.1.2