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Jad_Tabbara__J1's avatar
Jad_Tabbara__J1
Icon for Cirrostratus rankCirrostratus
May 16, 2019

Does F5 encrypts traffic internally from a VS to another VS ?

Dear community,    Context VS_Parent with clientssl + serverssl profiles and an iRule (that is responsible for routing the traffic to the child VSs based on the FQDN for example)  VS_Child1  has ...
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  • youssef1's avatar
    youssef1
    May 21, 2019

    Hi Jad,

     

    I had already asked myself the question.

     

    So Yes, F5 encrypts traffic routed from a VS_Parent to a VS_Child.

     

    I validate my supposition by removing SSL Client in VS_Child  and noticed that access to my service was not functional.

     

    Additional you can use my Debug irule (hosted in devcentral) that allow you to see that Cipher/protocol used in both VS (Child an parent).

     

    I advise you to process a ssldum using this kb:

     

    https://support.f5.com/csp/article/K10209

     

    So in child vs, initiate a basic capture:

     

    tcpdump -vvv -s 0 -nni external -w /var/tmp/www-ssl-client.cap host 10.1.1.100 and port 443

     

    then check ssl exchange:

     

    ssldump -nr /var/tmp/www-ssl-client.cap

     

    keep me in touch.

     

    regards,

youssef1's avatar
youssef1
Icon for Cumulonimbus rankCumulonimbus
May 21, 2019

Hi Jad,

 

I had already asked myself the question.

 

So Yes, F5 encrypts traffic routed from a VS_Parent to a VS_Child.

 

I validate my supposition by removing SSL Client in VS_Child  and noticed that access to my service was not functional.

 

Additional you can use my Debug irule (hosted in devcentral) that allow you to see that Cipher/protocol used in both VS (Child an parent).

 

I advise you to process a ssldum using this kb:

 

https://support.f5.com/csp/article/K10209

 

So in child vs, initiate a basic capture:

 

tcpdump -vvv -s 0 -nni external -w /var/tmp/www-ssl-client.cap host 10.1.1.100 and port 443

 

then check ssl exchange:

 

ssldump -nr /var/tmp/www-ssl-client.cap

 

keep me in touch.

 

regards,

  • Jad_Tabbara__J1's avatar
    Jad_Tabbara__J1
    Icon for Cirrostratus rankCirrostratus
    May 21, 2019

    Hello Youssef,

     

    Thanks for your answer. Using the "tcpdump + ssldump" I can see the SSL Handshake on the VS_CHILD...

     

    Before posting my question, I've done same capture using tcpdump, but I used Wireshark to see the SSL Handshake.

     

    My wireshark was not parsing the SSL traffic correctly, indeed using my colleague Wireshark we can see the SSL Handshake. I will re-install my wireshark to correct this.

     

    So the issue come from my wireshark :D

     

    Thank you you helped me to answer 2 questions in one :p

     

    Regards