Alcatel Carrier Internetworking Solutions 8800 User Manual

Page of 614
OmniSwitch 7700/7800/8800 Implementation
Troubleshooting Virtual Router Redundancy Protocol (VRRP)
page 13-4
OmniSwitch Troubleshooting Guide
September 2005
OmniSwitch 7700/7800/8800 Implementation
This section will cover how and what the OmniSwitch 7700/7800/8800s will support.
VRRP Security
The OmniSwitch7700/7800/8800 will support no authentication and simple text password. However the 
third method mentioned in the RFC, IP Authentication with HD5 HMAC is not supported in this the 
current release of VRRP software.
OmniSwitch VRRP Limitations
VRRP has a 255 VRRP Instance Limit in a chassis. In addition, VRRP is done in hardware for all VRRP 
IDs. However, you can only use a VRRP ID once. It cannot be reused in another VLAN. The RFC indi-
cated no limitation on reusing VRRP IDs in multiple VLANs, but OmniSwitch7700/7800/8800 does not 
support this in the first release. This could cause a problem if the VRRP Partner Router is limited on the 
number of Hardware Routed VRRP IDs like the OmniCore. 
The OmniCore is limited to 4 VRRP IDs (0-3) because it can route in hardware only 4 Virtual MAC 
addresses. These Virtual MAC addresses can be reused in separate VLANs however. When used with the 
OmniSwitch7700/7800/8800 switches with the same limitations as the OmniCore will need to be the 
stand-by router. If you do not design the network this way the limited VRRP Router will have to route in 
software. This will slow communications and may be too much for the device to handle. For example, the 
OmniCore EMM can handle only about 28 Kbps at the upper level.