General operating rules
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IP routing (IPv4) or IPv6 unicast-routing (IPv6) must be enabled on the router before enabling VRRP.
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IP must be enabled on a VLAN before creating a VR instance on the VLAN.
The VIP configured for one VR cannot be configured on another VR.
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changing a router from owner to backup, or the reverse, the VIP must be removed from the configuration.
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The priority configuration on an owner can be only 255. The priority configuration on a backup must be 254 or lower, the default being 100.
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Advertisement intervals:
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If a VRRP router has a different advertisement interval than a VRRP packet it receives, the router drops the packet. For this reason, the advertisement interval must be the same for the owner and all backups in the same VR.
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A VR exists within a single VLAN interface. If the VLAN is multinetted, a separate VR can be configured within the VLAN for each subnet. A VLAN allows up to 32 VRs (16 for the 2930F switch), and the switch allows up to 2048 VRs.
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All routers in the same VR must belong to the same network or subnet.
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The router supports the following maximums:
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32 VRs (16 for the 2930F switch) per VLAN in any combination of masters and backups
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512 (128 for the 2930F switch) IPv4 and IPv6 VRs in combination
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2046 Virtual IP addresses
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512 (128 for the 2930F switch) VR sessions on the switch
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512 (128 for the 2930F switch) VRRPv2 and VRRPv3 sessions, in any mix
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32 (16 for the 2930F switch) IP addresses per VR
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Each VR uses one MAC address as described under Virtual router MAC address.
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If an IP address is deleted on a VLAN interface, one of the following occurs:
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VR owner: If the VR uses the same IP address as a VIP, that IP address is deleted from the VR.
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VR backup: If the VR has a VIP in the same subnet as that of the deleted IP address, that VIP will be deleted from the VR.
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The VRRP backup router can respond to ping requests when the
virtual-ip-ping
feature is enabled. For more information, see Pinging the virtual IP of a backup router.