[c-nsp] Ping getting IPv6 address, though IPv6 is not enabled.

[Harold 'Buz' Dale]

Looks like your ping and nslookup commands are ipv6 aware.  DNS gives both
records and ping takes the v6 one.  Specify ³ping ipv4 address²
Like here:

RP/0/RSP0/CPU0:TELX1.BB#ping www.google.com
Fri Apr 17 12:41:27.530 EDT
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2607:f8b0:4002:c06::63, timeout is 2
seconds:
.....
Success rate is 0 percent (0/5)
RP/0/RSP0/CPU0:TELX1.BB#ping ipv4 www.google.com
Fri Apr 17 12:41:44.674 EDT
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 74.125.21.103, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms

Luck,
Buz


----------
buz.dale at usg.edu
Network Support Specialist University System of GA -IT Services.
706-583-2052 or (Toll Free in GA) 888-875-3697
 






On 4/16/15, 3:29 PM, "Joseph Mays" <mays at win.net> wrote:

>Got something going on on a router that seems strange. To me, anyway.
>
>I have a router that does not have IPv6 enabled, nor is IPv6 being used
>in the network it¹s on. ³ipv6² does not even occur anywhere in the config.
>
>On any addresses it looks up the IPv4 address fine, and can route to that
>address. But when I ping something like www.yahoo.com it grabs the IPv6
>address and tries to ping that. And fails, of course. How do I get it to
>stop preferring IPv6 addresses?
>
>core-gw1.noc#show ip route www.yahoo.com
>Translating "www.yahoo.com"...domain server (216.24.27.4) [OK]
>
>Routing entry for 98.139.128.0/17
>  Known via "bgp 7333", distance 20, metric 126041
>  Tag 174, type external
>  Last update from 38.122.142.5 1w0d ago
>  Routing Descriptor Blocks:
>  * 38.122.142.5, from 38.122.142.5, 1w0d ago
>      Route metric is 126041, traffic share count is 1
>      AS Hops 3
>
>core-gw1.noc#show run | include ping
>core-gw1.noc#show run | include icmp
>permit icmp any host 216.24.27.41
>core-gw1.noc#ping www.yahoo.com
>Translating "www.yahoo.com"...domain server (216.24.27.4) [OK]
>
>Type escape sequence to abort.
>Sending 5, 100-byte ICMP Echos to 2001:4998:58:C02::A9, timeout is 2
>seconds:
>.....
>Success rate is 0 percent (0/5)
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