Hello,
I have a 2800 router with IOS 15.0(1)M7 with no ipv6 connectivity. There are no
ipv6
addresses configured on any interfaces and i've added:
no ipv6 cef
no ipv6 unicast-routing
commands to config.
Nonetheless when I try to ping google the following happens:
c2800#ping google.com
Translating "google.com"...domain server (167.206.112.138) [OK]
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2607:F8B0:4006:801::1004, timeout is 2
seconds:
% No valid source address for destination
Success rate is 0 percent (0/1)
c2800#sh hosts
Default domain is aceinnovative.com
Name/address lookup uses domain service
Name servers are 167.206.112.138, 167.206.7.4
Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate
temp - temporary, perm - permanent
NA - Not Applicable None - Not defined
Host Port Flags Age Type Address(es)
google.com None (temp, OK) 0 IPv6 2607:F8B0:4006:801::1004
So when it sees AAAA record it tries to use it (regardless ipv6 routing has
been disabled), sees
there're no valid ipv6 addresses to use as source and fails, instead of trying
to use alternative
ipv4 addresses. It's also very strange that only IPv6 address has been cached
by resolver.
It looks like resolver discards any A record in the presence of AAAA.
FYI:
c2800#sh ipv6 interface brief
FastEthernet0/0 [up/up]
unassigned
FastEthernet0/1 [up/up]
unassigned
c2800#sh ipv6 route
IPv6 Routing Table - default - 1 entries
Codes: C - Connected, L - Local, S - Static, U - Per-user Static route
B - BGP, HA - Home Agent, MR - Mobile Router, R - RIP
I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea, IS - ISIS summary
D - EIGRP, EX - EIGRP external, ND - Neighbor Discovery
O - OSPF Intra, OI - OSPF Inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2
L FF00::/8 [0/0]
via Null0, receive
I wonder if this is a known issue, if there are any workarounds or if I'm
missing something?
Thank you,
Michael Ulitskiy
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