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@Aricg
Created August 8, 2014 17:23
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Docker Arp issues?
Ping from my docker image. first it doesnt work, then it does.
root@2ed081d6465f:/# ping 192.168.0.106
PING 192.168.0.106 (192.168.0.106) 56(84) bytes of data.
From 192.168.0.6 icmp_seq=1 Destination Host Unreachable
##
# 192.168.0.6 is not even a machine on the network!
##
^C
--- 192.168.0.106 ping statistics ---
10 packets transmitted, 0 received, +8 errors, 100% packet loss, time 9001ms
pipe 4
root@2ed081d6465f:/# ping 192.168.0.106
PING 192.168.0.106 (192.168.0.106) 56(84) bytes of data.
64 bytes from 192.168.0.106: icmp_seq=1 ttl=64 time=0.243 ms
64 bytes from 192.168.0.106: icmp_seq=2 ttl=64 time=0.107 ms
^C
--- 192.168.0.106 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 999ms
rtt min/avg/max/mdev = 0.107/0.175/0.243/0.068 ms
Tcpdump on the host: first not working, then working
$ sudo tcpdump -i docker0 | grep ARP
#Not Working
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on docker0, link-type EN10MB (Ethernet), capture size 65535 bytes
13:21:39.837078 ARP, Request who-has 192.168.0.101 (59:ea:c5:6b:c0:a8 (oui Unknown)) tell 192.168.0.1, length 46
13:21:49.940236 ARP, Request who-has 192.168.0.101 (d0:79:7b:06:c0:a8 (oui Unknown)) tell 192.168.0.1, length 46
#Working
13:22:52.918757 ARP, Request who-has 192.168.0.1 tell hyperion.local, length 28
13:22:52.919060 ARP, Reply 192.168.0.1 is-at 00:21:91:0f:0f:0d (oui Unknown), length 46
13:22:57.249098 ARP, Request who-has hyperion.local tell 192.168.0.7, length 28
13:22:57.249157 ARP, Reply hyperion.local is-at 28:d2:44:71:9f:30 (oui Unknown), length 28
13:23:02.262742 ARP, Request who-has 192.168.0.7 tell hyperion.local, length 28
13:23:02.262770 ARP, Reply 192.168.0.7 is-at 86:d3:a5:1f:a3:2a (oui Unknown), length 28
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