Ipv6 Vrrp Checksum Behavioral Differences; Vrrp Interoperability - Juniper EX9200 Features Manual

High Availability Feature Guide for EX9200 Switches

IPv6 VRRP Checksum Behavioral Differences

VRRP Interoperability

122
NOTE: VRRP (for IPv6) on routers that use Junos OS Release 12.2 and later
releases does not interoperate with VRRP (for IPv6) on routers with earlier
Junos OS releases because of the differences in VRRP checksum calculations.
See "IPv6 VRRP Checksum Behavioral Differences" on page
You must consider the following checksum differences when enabling IPv6 VRRP
networks:
In releases earlier than Junos OS Release 12.2, when VRRP for IPv6 is configured, the
VRRP checksum is calculated according to section 5.3.8 of RFC 3768, Virtual Router
Redundancy Protocol (VRRP).
Starting with Junos OS Release 12.2, when VRRP for IPv6 is configured, irrespective of
VRRPv3 being enabled or not, the VRRP checksum is calculated according to section
5.2.8 of RFC 5798, Virtual Router Redundancy Protocol (VRRP) Version 3 for IPv4 and
IPv6.
Moreover, the pseudoheader is included only when calculating the IPv6 VRRP checksum.
The pseudoheader is not included when calculating the IPv4 VRRP checksum.
To make the router with Junos OS Release 12.2 (or later Junos OS releases) IPv6 VRRP
interoperate with the router running a Junos OS release earlier than Release 12.2, include
the
checksum-without-pseudoheader
vrrp] hierarchy level in the router running Junos OS Release 12.2 or later.
The utility in Junos OS Release 12.2 and later calculates the VRRP checksum
tcpdump
according to RFC 5798, Virtual Router Redundancy Protocol (VRRP) Version 3 for IPv4
and IPv6. Therefore, when
older Junos OS releases (earlier than Junos OS Release 12.2), the
message is displayed:
23:20:32.657328 Out
...
-----original packet-----
00:00:5e:00:02:03 > 33:33:00:00:00:12, ethertype IPv6 (0x86dd), length
94: (class 0xc0, hlim 255, next-header: VRRP (112), length: 40)
fe80::224:dcff:fe47:57f > ff02::12: VRRPv3-advertisement 40: vrid=3 prio=100
intvl=100(centisec) (bad vrrp cksum b4e2!) addrs(2):
fe80::200:5eff:fe00:3,2001:4818:f000:14::1
You can ignore this message because it does not indicate VRRP failure.
In releases earlier than Junos OS Release 12.2, VRRP (IPv6) followed Internet draft
draft-ietf-vrrp-ipv6-spec-08, but checksum was calculated based on RFC 3768 section
configuration statement at the
tcpdump parses IPv6 VRRP packets that are received from
3333 0000 0012 0000 5e00 0203 86dd 6c00
0000 0028 70ff fe80 0000 0000 0000 0224
dcff fe47 057f ff02 0000 0000 0000 0000
0000 0000 0012 3103 6402 0064 b4e2 fe80
0000 0000 0000 0200 5eff fe00 0003 2001
4818 f000 0014 0000 0000 0000 0001
122.
[edit protocols
bad vrrp cksum
Copyright © 2017, Juniper Networks, Inc.