James Wright wrote:
Odds are it has to do with the ICMP packet size. Linux's default data string for a ping packet is 56 bits, add that to the 8 bit header and you get a 64 bit packet of data. I believe that Windows sends out a data string 24 bits in length, add the 8 bit header and you get a 32 bit packet. Use the -s option to specify the packet size as 24 bits and see if that works. Your equipment probably discards all ICMP packets that do not have a total of 24 bits after stripping the header. Good luck.
Well, it ended up being a wild couple of weeks, but I was finally
able to get back to the industrial system in question and try again.
Unfortunately, even changing the ping byte size didn't work. There's
definitely some kind of low-level structural difference between the
Linux and DOS pings -- I hubbed all three units (SuSE, XP, and
Industrial) and ran Ethereal to track pings in all directions. This
is what I got (using -s 32 on SuSE, and default on DOS):
SuSE ping to XP:
0000 00 11 11 5b fe 4b 00 40 45 12 91 c4 08 00 45 00 ...[.K.@E.....E.
0010 00 3c 00 02 40 00 40 01 50 b7 ac 10 c8 f1 ac 10 .<..@.@.P.......
0020 c8 f5 08 00 12 e7 bf 2a 00 03 7c 25 a7 43 11 91 .......*..|%.C..
0030 0c 00 08 09 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 ................
0040 16 17 18 19 1a 1b 1c 1d 1e 1f ..........
and XP's response:
0000 00 40 45 12 91 c4 00 11 11 5b fe 4b 08 00 45 00 .@E......[.K..E.
0010 00 3c ff 88 40 00 80 01 11 30 ac 10 c8 f5 ac 10 .<..@....0......
0020 c8 f1 00 00 1a e7 bf 2a 00 03 7c 25 a7 43 11 91 .......*..|%.C..
0030 0c 00 08 09 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 ................
0040 16 17 18 19 1a 1b 1c 1d 1e 1f ..........
Almost identical. But then there's XP-to-SuSE:
0000 00 40 45 12 91 c4 00 11 11 5b fe 4b 08 00 45 00 .@E......[.K..E.
0010 00 3c ff 76 00 00 80 01 51 42 ac 10 c8 f5 ac 10 .<.v....QB......
0020 c8 f1 08 00 3a 5c 02 00 11 00 61 62 63 64 65 66 ....:\....abcdef
0030 67 68 69 6a 6b 6c 6d 6e 6f 70 71 72 73 74 75 76 ghijklmnopqrstuv
0040 77 61 62 63 64 65 66 67 68 69 wabcdefghi
Same size, different structure. And SuSE's response:
0000 00 11 11 5b fe 4b 00 40 45 12 91 c4 08 00 45 00 ...[.K.@E.....E.
0010 00 3c 3c 45 00 00 40 01 54 74 ac 10 c8 f1 ac 10 .<