Dell Force10 S4810P - Page 1100

1100 | Virtual Router Redundancy Protocol (VRRP)
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Though FTOS on E-Series supports unlimited VRRP groups, default VRRP settings may affect the
maximum number of groups that can be configured and work efficiently, as a result of hardware throttling
VRRP advertisement packets reaching the RP2 processor on the E-Series, the CP on the C-Series, S4810,
S55, and S60, or the FP on the S25/S50. To avoid throttling VRRP advertisement packets, Dell Force10
recommends you to increase the VRRP advertisement interval to a value higher than the default value of 1
second. The recommendations are as follows:
The recommendations in Table 55-1 may vary depending on various factors like ARP broadcasts, IP
broadcasts, or STP before changing the advertisement interval. When the number of packets processed by
RP2/CP/FP processor increases or decreases based on the dynamics of the network, the advertisement
intervals in may increase or decrease accordingly.
Table 55-1. Recommended VRRP Advertise Intervals
Total VRRP Groups
Recommended Advertise Interval Groups/Interface
E-Series C-Series
S-Series
(S25, S50)
E-Series
ExaScale
E-Series
TeraScale C-Series
S-Series
(S25, S50)
Less than 250 1 second 1 second 1 second 512 255 12 12
Between 250 and 450 2 seconds 2 - 3 seconds 2 - 3 seconds 512 255 24 24
Between 450 and 600 3 seconds 4 seconds 3 - 4 seconds 512 255 36 36
Between 600 and 800 4 seconds 5 seconds 4 seconds 512 255 48 48
Between 800 and 1000 5 seconds 5 seconds 5 seconds 512 255 84 84
Between 1000 and 1200 7 seconds 7 seconds 7 seconds 512 255 100 100
Between 1200 and 1500 8 seconds 8 seconds 8 seconds 512 255 120 120
Table 55-2. Recommended VRRP Advertise Intervals on the S4810, S55, S60
Total VRRP Groups
Recommended Advertise Interval Groups/Interface
S4810 S55 S60 S4810 S55 S60
Less than 250 1 second 1 second 1 second 512 100 100
Between 250 and 450 2 - 3 seconds 2 - 3 seconds 2 - 3 seconds 512 100 100
Between 450 and 600 3 - 4 seconds 3 - 4 seconds 3 - 4 seconds 512 100 100
Between 600 and 800 4 seconds 4 seconds 4 seconds 512 100 100
Between 800 and 1000 5 seconds 5 seconds 5 seconds 512 100 100
Between 1000 and 1200 7 seconds 7 seconds 7 seconds 512 100 100
Between 1200 and 1500 8 seconds 8 seconds 8 seconds 512 100 100
CAUTION: Increasing the advertisement interval increases the VRRP Master dead interval, resulting in an
increased failover time for Master/Backup election. Take extra caution when increasing the advertisement
interval, as the increased dead interval may cause packets to be dropped during that switch-over time.