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thoughts
Apprentice
Joined: 15 Apr 2004
Posts: 153
Location: Pennsylvania
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 Posted: Wed Dec 08, 2004 1:02 am Post subject: two networked boxes won't talk |
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I have two boxes networked that both communicate 100% fine with the outside world and other machines on their LAN, but they totally won't talk to each other. They won't ping each other and I can't ssh from one to the other.
These aren't Gentoo systems (one Fedora, one RH... and what I wouldn't give to be able to install Gentoo on both of 'em...) but this is the best place around to get help, and I think this is a distro-agnostic problem -- it seems pretty low-level. I'm fairly experienced with Linux but everything I've tried has failed to make them talk.
So... here is some info on box1:
| Code: | [0555][/tmp/box1]# ifconfig eth0|grep "inet addr"
inet addr:10.0.0.12 Bcast:10.0.0.255 Mask:255.255.255.0
[0555][/tmp/box1]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.0.0.0 * 255.255.255.0 U 0 0 0 eth0
127.0.0.0 * 255.0.0.0 U 0 0 0 lo
default 10.0.0.1 0.0.0.0 UG 0 0 0 eth0
[0555][/tmp/box1]# ping -c 1 10.0.0.12
PING 10.0.0.12 (10.0.0.12) from 10.0.0.12 : 56(84) bytes of data.
64 bytes from 10.0.0.12: icmp_seq=1 ttl=64 time=0.055 ms
--- 10.0.0.12 ping statistics ---
1 packets transmitted, 1 received, 0% loss, time 0ms
rtt min/avg/max/mdev = 0.055/0.055/0.055/0.000 ms
[0555][/tmp/box1]# ping -c 1 10.0.0.13
PING 10.0.0.13 (10.0.0.13) from 10.0.0.12 : 56(84) bytes of data.
--- 10.0.0.13 ping statistics ---
1 packets transmitted, 0 received, 100% loss, time 0ms
[0556][/tmp/box1]# cat /etc/hosts|grep localhost
127.0.0.1 localhost.localdomain localhost |
And the same info on box2:
| Code: | [1950][/tmp/box2]# ifconfig eth0|grep "inet addr"
inet addr:10.0.0.13 Bcast:10.0.0.255 Mask:255.255.255.0
[1954][/tmp/box2]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.0.0.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
default 10.0.0.1 0.0.0.0 UG 0 0 0 eth0
[1954][/tmp/box2]# ping -c 1 10.0.0.13
PING 10.0.0.13 (10.0.0.13) 56(84) bytes of data.
64 bytes from 10.0.0.13: icmp_seq=0 ttl=64 time=0.053 ms
--- 10.0.0.13 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.053/0.053/0.053/0.000 ms, pipe 2
[1955][/tmp/box2]# ping -c 1 10.0.0.12
PING 10.0.0.12 (10.0.0.12) 56(84) bytes of data.
--- 10.0.0.12 ping statistics ---
1 packets transmitted, 0 received, 100% packet loss, time 0ms
[1955][/tmp/box2]# cat /etc/hosts|grep localhost
127.0.0.1 localhost.localdomain localhost |
So, you can see that each one can ping itself (and can ping any other system on the net too), but they can't ping each other. Same for ssh, as I said.
The only difference that jumps out is the 127.0.* vs 168.254.* in the route output. That looks possibly suspicious, but I don't know if that would cause this problem, since they'd be using the 10.* route to communicate.
Any ideas here would be greatly appreciated.
-Anthony DiSante
http://nodivisions.com/ |
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adsmith
Veteran
Joined: 26 Sep 2004
Posts: 1386
Location: NC, USA
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| Posted: Wed Dec 08, 2004 1:13 am Post subject: |
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do you by chance have firewalls on each which block ping specifically (this is common)?
try nmap'ing them. |
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zrubi
n00b
Joined: 04 Mar 2004
Posts: 40
Location: Budapest, Hungary
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| Posted: Wed Dec 08, 2004 1:14 am Post subject: Re: two networked boxes won't talk |
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| thoughts wrote: |
The only difference that jumps out is the 127.0.* vs 168.254.* in the route output. That looks possibly suspicious, but I don't know if that would cause this problem, since they'd be using the 10.* route to communicate.
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The box2 has no 'lo' interface?!
It can be the problem because every networking stuff need this. |
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thoughts
Apprentice
Joined: 15 Apr 2004
Posts: 153
Location: Pennsylvania
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| Posted: Wed Dec 08, 2004 1:26 am Post subject: |
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| adsmith wrote: | do you by chance have firewalls on each which block ping specifically (this is common)?
try nmap'ing them. |
It's not just ping. They can't ssh into each other either, but ssh-ing from other machines works fine to both of them.
Here's nmap from box1 to box2:
| Code: | [0608][/tmp/box1]# nmap -P0 -T insane 10.0.0.13
Starting nmap V. 2.54BETA31 ( www.insecure.org/nmap/ )
Skipping host box2 (10.0.0.13) due to host timeout
Nmap run completed -- 1 IP address (1 host up) scanned in 75 seconds |
And nmap from box2 to box1:
| Code: | [2006][/tmp/box2]# nmap -P0 -T insane 10.0.0.12
Starting nmap 3.70 ( http://www.insecure.org/nmap/ ) at 2004-12-07 20:19 EST
All 1660 scanned ports on box1 (10.0.0.12) are: filtered
MAC Address: XX:XX:XX:XX:XX:XX (NIC Manufacturer)
Nmap run completed -- 1 IP address (1 host up) scanned in 84.664 seconds |
So... looks like box2 can see box1 slightly, but sees everything filtered, even though ssh and http are open. Box1 can't see box2.
-Anthony DiSante
http://nodivisions.com/ |
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thoughts
Apprentice
Joined: 15 Apr 2004
Posts: 153
Location: Pennsylvania
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| Posted: Wed Dec 08, 2004 1:31 am Post subject: Re: two networked boxes won't talk |
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| zrubi wrote: | | thoughts wrote: |
The only difference that jumps out is the 127.0.* vs 168.254.* in the route output. That looks possibly suspicious, but I don't know if that would cause this problem, since they'd be using the 10.* route to communicate.
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The box2 has no 'lo' interface?!
It can be the problem because every networking stuff need this. |
Hm, yeah, there is no "lo" in the route output, but ifconfig does show it:
| Code: | [2033][/tmp/box2]# ifconfig lo
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:7892 errors:0 dropped:0 overruns:0 frame:0
TX packets:7892 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:3493198 (3.3 Mb) TX bytes:3493198 (3.3 Mb) |
-Anthony DiSante
http://nodivisions.com/ |
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zrubi
n00b
Joined: 04 Mar 2004
Posts: 40
Location: Budapest, Hungary
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| Posted: Wed Dec 08, 2004 1:33 am Post subject: Re: two networked boxes won't talk |
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| thoughts wrote: |
Hm, yeah, there is no "lo" in the route output, but ifconfig does show it:
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Ok, just try to make a route for lo and see what happened... |
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thoughts
Apprentice
Joined: 15 Apr 2004
Posts: 153
Location: Pennsylvania
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| Posted: Wed Dec 08, 2004 1:39 am Post subject: |
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| Code: | [2042][/tmp/box2]# route add -net 127.0.0.0
SIOCADDRT: Invalid argument |
Something's broke, apparently...
-Anthony DiSante
http://nodivisions.com/ |
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thoughts
Apprentice
Joined: 15 Apr 2004
Posts: 153
Location: Pennsylvania
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| Posted: Wed Dec 08, 2004 5:46 am Post subject: |
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| thoughts wrote: | | Code: | [2042][/tmp/box2]# route add -net 127.0.0.0
SIOCADDRT: Invalid argument |
Something's broke, apparently...
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OK, so that's the command that the route manpage says to use, but it doesn't work; the correct command is "route add -net 127.0.0.0 netmask 255.0.0.0 lo". So now I do have a route through lo. But this hasn't fixed the problem; the two systems still can't ping or ssh each other.
-Anthony DiSante
http://nodivisions.com/ |
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zrubi
n00b
Joined: 04 Mar 2004
Posts: 40
Location: Budapest, Hungary
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| Posted: Wed Dec 08, 2004 12:32 pm Post subject: |
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| thoughts wrote: |
So now I do have a route through lo. But this hasn't fixed the problem; the two systems still can't ping or ssh each other.
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Try to arping each other, and dump the traffic with tcpdump... |
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thoughts
Apprentice
Joined: 15 Apr 2004
Posts: 153
Location: Pennsylvania
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| Posted: Wed Dec 08, 2004 11:10 pm Post subject: |
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| zrubi wrote: | | Try to arping each other, and dump the traffic with tcpdump... |
OK, each box CAN arping the other, and it receives the responses OK. Here's the tcpdump output -- I'm not too familiar with tcpdump, but this seems to indicate that they are communicating OK at this low level?
while box1 arpings 10.0.0.13:
| Code: | 03:49:35.914659 802.1d config 812c.00:0f:8f:xx:xx:00.8173 root 812c.00:0f:8f:yy:yy:80 pathcost 4 age 2 max 20 hello 2 fdelay 15
03:49:36.836948 arp who-has box2 (0:8:74:vv:vv:vv) tell box1
03:49:36.837303 arp reply box2 is-at 0:8:74:vv:vv:vv |
while box2 arpings 10.0.0.12:
| Code: | 17:42:23.906554 802.1d config 812c.00:0f:8f:xx:xx:00.8172 root 812c.00:0f:8f:yy:yy:80 pathcost 4 age 2 max 20 hello 2 fdelay 15
17:42:24.344927 arp who-has box1 (00:08:74:zz:zz:zz) tell box2
17:42:24.345167 arp reply box1 is-at 00:08:74:zz:zz:zz |
-Anthony DiSante
http://nodivisions.com/ |
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zrubi
n00b
Joined: 04 Mar 2004
Posts: 40
Location: Budapest, Hungary
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| Posted: Thu Dec 09, 2004 6:30 am Post subject: |
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| thoughts wrote: |
OK, each box CAN arping the other, and it receives the responses OK. Here's the tcpdump output -- I'm not too familiar with tcpdump, but this seems to indicate that they are communicating OK at this low level?
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Yes, that's right. 
The nex steps are:
- try the same with (normal) ping.
- try the same with a TCP session, like ssh
And let me see the results too. |
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thoughts
Apprentice
Joined: 15 Apr 2004
Posts: 153
Location: Pennsylvania
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| Posted: Thu Dec 09, 2004 7:27 am Post subject: |
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| zrubi wrote: |
- try the same with (normal) ping.
- try the same with a TCP session, like ssh
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OK, here is tcpdump from box1 while it's pinging box2 (and the ping command shows 100% packet loss):
| Code: | 01:52:36.301095 box1 > box2: icmp: echo request (DF)
01:52:36.558211 802.1d config 812c.00:0f:8f:xx:xx:xx.8173 root 812c.00:0f:8f:yy:yy:yy pathcost 4 age 2 max 20 hello 2 fdelay 15
01:52:37.313289 box1 > box2: icmp: echo request (DF)
01:52:38.313294 box1 > box2: icmp: echo request (DF)
01:52:38.563546 802.1d config 812c.00:0f:8f:xx:xx:xx.8173 root 812c.00:0f:8f:yy:yy:yy pathcost 4 age 2 max 20 hello 2 fdelay 15
01:52:39.313288 box1 > box2: icmp: echo request (DF)
01:52:40.050711 iso esis aa:0:4:0:1:14 > 9:0:2b:0:0:5 esh len=43
020a 4900 05aa 0004 0001 1420 0a49 0005
aa00 0400 0114 2100 0000 0000 0000 0000
0000
01:52:40.313292 box1 > box2: icmp: echo request (DF)
01:52:40.570378 802.1d config 812c.00:0f:8f:xx:xx:xx.8173 root 812c.00:0f:8f:yy:yy:yy pathcost 4 age 2 max 20 hello 2 fdelay 15
01:52:41.299508 arp who-has box2 tell box1
01:52:41.299619 arp reply box2 is-at 0:11:92:vv:vv:vv
01:52:41.313289 box1 > box2: icmp: echo request (DF)
01:52:42.313283 box1 > box2: icmp: echo request (DF)
01:52:42.573963 802.1d config 812c.00:0f:8f:xx:xx:xx.8173 root 812c.00:0f:8f:yy:yy:yy pathcost 4 age 2 max 20 hello 2 fdelay 15
01:52:43.313284 box1 > box2: icmp: echo request (DF)
01:52:44.313281 box1 > box2: icmp: echo request (DF) |
And here is tcpdump from box1 while it's trying to ssh into box2 (which fails) -- this is only about 90 seconds' worth, and I've removed the "config" lines since they seem unimportant and never change; let me know if you'd like to see them:
| Code: | 02:07:54.650026 box1.32885 > box2.ssh: S 4111708010:4111708010(0) win 5840 <mss 1460,sackOK,timestamp 14388046 0,nop,wscale 0> (DF)
02:07:56.628482 0:f:8f:93:d5:87 0:f:8f:93:d5:87 loopback 60:
0000 0100 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000
02:07:56.633352 iso esis aa:0:4:0:1:14 > 9:0:2b:0:0:5 esh len=43
020a 4900 05aa 0004 0001 1420 0a49 0005
aa00 0400 0114 2100 0000 0000 0000 0000
0000
02:07:57.649136 box1.32885 > box2.ssh: S 4111708010:4111708010(0) win 5840 <mss 1460,sackOK,timestamp 14389582 0,nop,wscale 0> (DF)
02:07:59.350030 aa:0:4:0:1:14 9:0:2b:0:0:f lat 228:
2808 0505 0503 edf7 dc05 3c02 20ff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ff06 5343
4556 414c 4020 5765 6c63 6f6d 6520 746f
204f 7065 6e56 4d53 2028 544d 2920 416c
7068
02:07:59.649119 arp who-has box2 tell box1
02:07:59.649340 arp reply box2 is-at 0:11:92:yy:yy:yy
02:08:03.649137 box1.32885 > box2.ssh: S 4111708010:4111708010(0) win 5840 <mss 1460,sackOK,timestamp 14392654 0,nop,wscale 0> (DF)
02:08:04.580342 iso esis aa:0:4:0:1:14 > 9:0:2b:0:0:5 esh len=43
020a 4900 05aa 0004 0001 1420 0a49 0005
aa00 0400 0114 2100 0000 0000 0000 0000
0000
02:08:06.626412 0:f:8f:93:d5:87 0:f:8f:93:d5:87 loopback 60:
0000 0100 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000
02:08:12.729379 iso esis aa:0:4:0:1:14 > 9:0:2b:0:0:5 esh len=43
020a 4900 05aa 0004 0001 1420 0a49 0005
aa00 0400 0114 2100 0000 0000 0000 0000
0000
02:08:15.649135 box1.32885 > box2.ssh: S 4111708010:4111708010(0) win 5840 <mss 1460,sackOK,timestamp 14398798 0,nop,wscale 0> (DF)
02:08:16.639210 0:f:8f:93:d5:87 0:f:8f:93:d5:87 loopback 60:
0000 0100 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000
02:08:21.883642 iso esis aa:0:4:0:1:14 > 9:0:2b:0:0:5 esh len=43
020a 4900 05aa 0004 0001 1420 0a49 0005
aa00 0400 0114 2100 0000 0000 0000 0000
0000
02:08:22.250621 CDP v2, ttl=180s
DevID 'StackOne'
Addr (2): IPv4 192.168.1.3 IPv4 192.168.1.3
PortID 'FastEthernet8/0/5'
CAP 0x29[!cdp]
02:08:26.645388 0:f:8f:93:d5:87 0:f:8f:93:d5:87 loopback 60:
0000 0100 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000
02:08:31.340659 iso esis aa:0:4:0:1:14 > 9:0:2b:0:0:5 esh len=43
020a 4900 05aa 0004 0001 1420 0a49 0005
aa00 0400 0114 2100 0000 0000 0000 0000
0000
02:08:36.655078 0:f:8f:93:d5:87 0:f:8f:93:d5:87 loopback 60:
0000 0100 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000
02:08:39.188064 iso esis aa:0:4:0:1:14 > 9:0:2b:0:0:5 esh len=43
020a 4900 05aa 0004 0001 1420 0a49 0005
aa00 0400 0114 2100 0000 0000 0000 0000
0000
02:08:39.649135 box1.32885 > box2.ssh: S 4111708010:4111708010(0) win 5840 <mss 1460,sackOK,timestamp 14411086 0,nop,wscale 0> (DF)
02:08:46.656620 0:f:8f:93:d5:87 0:f:8f:93:d5:87 loopback 60:
0000 0100 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000
02:08:48.945840 iso esis aa:0:4:0:1:14 > 9:0:2b:0:0:5 esh len=43
020a 4900 05aa 0004 0001 1420 0a49 0005
aa00 0400 0114 2100 0000 0000 0000 0000
0000
02:08:50.550209 aa:0:4:0:1:14 ab:0:0:2:0:0 moprc 151:
8700 0700 0000 0100 0304 0000 0200 0241
0007 0006 000f 202b 51e1 6400 01cc 9001
0101 c800 01ff c900 0441 564d 53ca 0008
5637 2e33 2d32 2020 cb00 0853 4345 5641
4c20 20cc 0004 ff07 0000 cd00 0829 0032
0701
02:08:50.550211 aa:0:4:0:1:14 > ab:0:0:2:0:0 sap aa ui/C
>>> Unknown IPX Data: (71 bytes)
[000] 00 01 00 03 04 00 00 02 00 02 41 00 07 00 06 00 ........ ..A.....
[010] 0F 20 2B 51 E1 64 00 01 CC 90 01 01 01 C8 00 01 . +Q.d.. ........
[020] FF C9 00 04 41 56 4D 53 CA 00 08 56 37 2E 33 2D ....AVMS ...V7.3-
[030] 32 20 20 CB 00 08 53 43 45 56 41 4C 20 20 CC 00 2 ...SC EVAL ..
[040] 04 FF 07 00 00 CD 00 .......
len=132
02:08:56.669044 0:f:8f:93:d5:87 0:f:8f:93:d5:87 loopback 60:
0000 0100 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000
02:08:57.598051 iso esis aa:0:4:0:1:14 > 9:0:2b:0:0:5 esh len=43
020a 4900 05aa 0004 0001 1420 0a49 0005
aa00 0400 0114 2100 0000 0000 0000 0000
0000
02:08:59.710094 aa:0:4:0:1:14 9:0:2b:0:0:f lat 228:
2808 0505 0503 edf7 dc05 3c02 20ff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ff06 5343
4556 414c 4020 5765 6c63 6f6d 6520 746f
204f 7065 6e56 4d53 2028 544d 2920 416c
7068
02:09:06.667099 0:f:8f:93:d5:87 0:f:8f:93:d5:87 loopback 60:
0000 0100 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000
02:09:06.953485 iso esis aa:0:4:0:1:14 > 9:0:2b:0:0:5 esh len=43
020a 4900 05aa 0004 0001 1420 0a49 0005
aa00 0400 0114 2100 0000 0000 0000 0000
0000
02:09:16.679774 0:f:8f:93:d5:87 0:f:8f:93:d5:87 loopback 60:
0000 0100 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000
02:09:16.712385 iso esis aa:0:4:0:1:14 > 9:0:2b:0:0:5 esh len=43
020a 4900 05aa 0004 0001 1420 0a49 0005
aa00 0400 0114 2100 0000 0000 0000 0000
0000
02:09:22.275068 CDP v2, ttl=180s
DevID 'StackOne'
Addr (2): IPv4 192.168.1.3 IPv4 192.168.1.3
PortID 'FastEthernet8/0/5'
CAP 0x29[!cdp]
02:09:26.096385 arp who-has 10.0.0.1 tell box1
02:09:26.096561 arp reply 10.0.0.1 is-at 0:11:92:yy:yy:yy
02:09:26.671458 iso esis aa:0:4:0:1:14 > 9:0:2b:0:0:5 esh len=43
020a 4900 05aa 0004 0001 1420 0a49 0005
aa00 0400 0114 2100 0000 0000 0000 0000
0000
02:09:26.686075 0:f:8f:93:d5:87 0:f:8f:93:d5:87 loopback 60:
0000 0100 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000
02:09:27.649135 box1.32885 > box2.ssh: S 4111708010:4111708010(0) win 5840 <mss 1460,sackOK,timestamp 14435662 0,nop,wscale 0> (DF)
02:09:32.649118 arp who-has box2 tell box1
02:09:32.649355 arp reply box2 is-at 0:11:92:yy:yy:yy |
-Anthony DiSante
http://nodivisions.com/ |
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zrubi
n00b
Joined: 04 Mar 2004
Posts: 40
Location: Budapest, Hungary
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| Posted: Thu Dec 09, 2004 8:36 am Post subject: |
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| thoughts wrote: |
OK, here is tcpdump from box1 while it's pinging box2 (and the ping command shows 100% packet loss):
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Well, there is to much garbage...
try this:
| Code: | | tcpdump -ni eth0 host 10.0.0.12 or host 10.0.0.13 or icmp or arp |
Please include only the 'other' ends output... |
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thoughts
Apprentice
Joined: 15 Apr 2004
Posts: 153
Location: Pennsylvania
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| Posted: Thu Dec 09, 2004 9:14 am Post subject: |
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| zrubi wrote: | | thoughts wrote: |
OK, here is tcpdump from box1 while it's pinging box2 (and the ping command shows 100% packet loss):
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Well, there is to much garbage...
try this:
| Code: | | tcpdump -ni eth0 host 10.0.0.12 or host 10.0.0.13 or icmp or arp |
Please include only the 'other' ends output... |
The other (destination) end has no output from tcpdump at all, whether pinging or sshing. (But it did when arping-ing.)
-Anthony DiSante
http://nodivisions.com/ |
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zrubi
n00b
Joined: 04 Mar 2004
Posts: 40
Location: Budapest, Hungary
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| Posted: Thu Dec 09, 2004 10:35 am Post subject: |
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| thoughts wrote: |
The other (destination) end has no output from tcpdump at all, whether pinging or sshing. (But it did when arping-ing.)
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Did you try both directions? (10.0.0.12->10.0.0.13 and 10.0.0.13->10.0.0.12)
Same results?
It's seems there is a lower level problem, possible around your switch or other network device...
anyway, try to connect them with a cross cable, and test it. |
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thoughts
Apprentice
Joined: 15 Apr 2004
Posts: 153
Location: Pennsylvania
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| Posted: Mon Dec 13, 2004 5:35 am Post subject: |
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| zrubi wrote: | | thoughts wrote: | The other (destination) end has no output from tcpdump at all, whether pinging or sshing. (But it did when arping-ing.)
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Did you try both directions? (10.0.0.12->10.0.0.13 and 10.0.0.13->10.0.0.12)
Same results? |
Yes, both directions give the same result. I ran it again while pinging, and waited a little longer, and eventually tcpdump shows this on the source machine:
| Code: | 00:22:28.932913 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 0
00:22:29.932471 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 1
00:22:30.933244 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 2
00:22:31.933027 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 3
00:22:32.932843 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 4
00:22:33.932637 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 5
00:22:34.932429 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 6
00:22:35.932248 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 7
00:22:36.932029 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 8
00:22:37.931827 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 9
00:22:38.931634 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 10
00:22:39.931426 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 11
00:22:40.931231 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 12
00:22:41.931036 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 13
00:22:42.930828 IP 10.0.0.13 > 10.0.0.12: icmp 64: echo request seq 14
...
|
So that shows that there are no responses from the dest machine, and the ping command reports 100% packet loss.
| zrubi wrote: | It's seems there is a lower level problem, possible around your switch or other network device...
anyway, try to connect them with a cross cable, and test it. |
These two machines are on a big cisco router. I took them off it and connected them to a small (4-port) D-Link personal switch, and the problem is exactly the same.
-Anthony DiSante
http://nodivisions.com/ |
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