As you know, I sometimes run into seemingly inexplicable anomalies, for
which I do not know what corroborative evidence is appropriate.
This is another one of those ;>
[1] My question is, *how* can an icmp packet get through DCD _and_ get
to an internal, NAT'ed system ???
[2] Stock DCD, regarding icmp -- no mods.
[3] LEAF/LRP development box:
# uname -a
Linux Frigg 2.2.19-3-LEAF #4 Sun Dec 16 18:10:46 CST 2001 i586 unknown
# ifconfig
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:3924 Metric:1
RX packets:28 errors:0 dropped:0 overruns:0 frame:0
TX packets:28 errors:0 dropped:0 overruns:0 carrier:0
Collisions:0
eth0 Link encap:Ethernet HWaddr 00:60:97:67:74:9A
inet addr:192.168.123.130 Bcast:192.168.123.255
Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:3274464 errors:118 dropped:0 overruns:122
frame:118
TX packets:935885 errors:0 dropped:0 overruns:0 carrier:0
Collisions:0
Interrupt:11 Base address:0xd800
[4] Strange message logged this morning:
# grep icmp /var/log/syslog
May 1 07:02:55 Frigg icmplogd: destination unreachable from
[12.244.72.230]
May 1 07:09:19 Frigg icmplogd: destination unreachable from
[12.244.72.230]
[5] 12.244.72.230 is somewhere on AT&T network; but, doesn't have a dns
name nor reverse lookup:
# dnsname 12.244.72.230
# dnsqr any 230.72.244.12.in-addr.arpa
255 230.72.244.12.in-addr.arpa:
44 bytes, 1+0+0+0 records, response, authoritative, nxdomain
query: 255 230.72.244.12.in-addr.arpa
# dnsqr any 72.244.12.in-addr.arpa
255 72.244.12.in-addr.arpa:
40 bytes, 1+0+0+0 records, response, noerror
query: 255 72.244.12.in-addr.arpa
# dnsqr any 244.12.in-addr.arpa
255 244.12.in-addr.arpa:
198 bytes, 1+5+0+0 records, response, noerror
query: 255 244.12.in-addr.arpa
answer: 244.12.in-addr.arpa 172800 NS cbru.br.ns.els-gms.att.net
answer: 244.12.in-addr.arpa 172800 NS dbru.br.ns.els-gms.att.net
answer: 244.12.in-addr.arpa 172800 NS cmtu.mt.ns.els-gms.att.net
answer: 244.12.in-addr.arpa 172800 NS dmtu.mt.ns.els-gms.att.net
answer: 244.12.in-addr.arpa 172800 SOA cbru.br.ns.els-gms.att.net
rm-hostmaster.ems.att.com 29 86400 10000 600000 172800
What do you think?
--
Best Regards,
mds
mds resource
888.250.3987
Dare to fix things before they break . . .
Our capacity for understanding is inversely proportional to how much we
think we know. The more I know, the more I know I don't know . . .
