Juniper EX9200 Features Manual page 151

Copyright © 2017, Juniper Networks, Inc.
When configuring a virtual IP address, consider the following:
The virtual IP address must be the same for all routing platforms in the VRRP group.
If you configure a virtual IP address to be the same as the physical interface's address,
the interface becomes the master virtual router for the group. In this case, you must
configure the priority to be 255, and you must configure preemption by including the
preempt statement.
If the virtual IP address you choose is not the same as the physical interface's address,
you must ensure that the virtual IP address does not appear anywhere else in the
routing platform's configuration. Verify that you do not use this address for other
interfaces, for the IP address of a tunnel, or for the IP address of static ARP entries.
You cannot configure a virtual IP address to be the same as the interface's address for
an aggregated Ethernet interface. This configuration is not supported.
For VRRP for IPv6, the
EUI-64
Detection (DAD) process will not run for virtual IPv6 addresses.
You cannot configure the same virtual IP address on interfaces that belong to the same
logical system and routing instance combination. However, you can configure the same
virtual IP address on interfaces that belong to different logical systems and routing
instance combinations.
In determining what priority will make a given routing platform in a VRRP group a master
or backup, consider the following:
You can force assignment of master and backup routers using priorities from 1 through
255, where 255 is the highest priority.
The priority value for the VRRP router that owns the IP address(es) associated with
the virtual router must be 255.
VRRP routers backing up a virtual router must use priority values from 1 through 254.
The default priority value for VRRP routers backing up a virtual router is 100.
Are there tracked interfaces or routes with priority costs?
The priority cost is the value associated with a tracked logical interface or route that
is to be subtracted from the configured VRRP priority when the tracked logical interface
or route goes down, forcing a new master router election. The value of a priority cost
can be from 1 through 254. The sum of the priority costs for all tracked logical interfaces
or routes must be less than or equal to the configured priority of the VRRP group.
NOTE: Mixed tagging (configuring two logical interfaces on the same Ethernet
port, one with single-tag framing and one with dual-tag framing) is supported
only for interfaces on Gigabit Ethernet IQ2 and IQ PICs. If you include the
flexible-vlan-tagging
level for a VRRP-enabled interface on a PIC that does not support mixed
tagging, VRRP on that interface is disabled. In the output of the
operational command, the interface status is listed as
summary
option cannot be used. In addition, the Duplicate Address
statement at the [edit interfaces interface-name]
Chapter 14: Configuring VRRP
hierarchy
show vrrp
.
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