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Stefan_Klotz_85's avatar
Stefan_Klotz_85
Icon for Cirrus rankCirrus
Jul 14, 2014
Solved

TCP monitor with sending a byte sequence

One of our customers is using a TCP/IP based application and instead of using the default TCP monitor, they will check their application with sending a specific byte sequence after the TCP connect. I...
application delivery
availability
LTM
TMOS
  • 0x0ff_info_1420's avatar
    0x0ff_info_1420
    Jul 23, 2014

    Why do you use -l parameter ? It's mean listen so, your commands wait for connexion and send your binary payload.

     

    The nc error message tell you that you can't listen on an interface you don't own. Till now, I didn't know we could specify the address. :p

     

    But what you do there is not what I wanted to explain to you in my first post. I told you (but not clearly, i admit :p) that you could use regular TCP monitor in TMSH or GUI. In the field Send String and in the field Receive String you can actually use the escaped string. ;) More simple than with the nc script no ?

     

Stefan_Klotz's avatar
Stefan_Klotz
Icon for Cumulonimbus rankCumulonimbus
Jul 23, 2014

Hi again,

I'm now able to perform some testing, but fighting with below error:

nc: Cannot assign requested address

I tried these two commands, which both ends up with the same error:

echo -ne "\x3e\x7a\x21\x53\x46\x2e\x0e\x4a\xa4\xa7\x51\xfd\x36\xfe\x71\x4e\x80\x00\x65\x63\x68\x6f\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x70\x69\x6e\x67\xff\xff\xff\xff" | nc -l 2620:0000:0C10:F501:0000:0002:0AFD:61AB 55555

and

echo "3e7a2153462e0e4aa4a751fd36fe714e80006563686f0000000000000000000000000000000000000400000070696e67ffffffff" | xxd -r -p | nc -l 2620:0000:0C10:F501:0000:0002:0AFD:61AB 55555

The IPv6-address is being used, because we have route domains in place. Any idea, what I'm doing wrong?

Thank you!

Ciao Stefan 🙂