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siru_129409's avatar
siru_129409
Icon for Nimbostratus rankNimbostratus
Jun 25, 2015

Retain the original source ip address on SMTP VS

Hi

 

I have a SMTP virtual Server with snat pool enable on it. the problem is that now the Microsoft Exchange team want to see the real client ip address on their servers, how can i achieve it.

 

my F5 software version is 11.4

 

any help would be highly appreciated.

 

application delivery
deployment
devops
iRules
LTM
microsoft
smtp

9 Replies

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  • TechT's avatar
    TechT
    Icon for Nimbostratus rankNimbostratus
    Jun 25, 2015

    Hi Siru, you can try inserting [IP::client_addr] in the xff(x-forward-for) header using HTTP profile or an iRule.

     

  • siru_129409's avatar
    siru_129409
    Icon for Nimbostratus rankNimbostratus
    Jun 25, 2015

    Hi Manesh, thanks for your reply

     

    yes, for http VS we can enable xff, are you sure about the SMTP VS...? or if you have any i rule for this can you please share..?

     

  • amolari's avatar
    amolari
    Icon for Cirrus rankCirrus
    Jun 25, 2015

    do not use snat for that VS. You might have to change your network settings/design.

     

  • siru_129409's avatar
    siru_129409
    Icon for Nimbostratus rankNimbostratus
    Jun 25, 2015

    Hi Amolari, Actually i want to change my network settings, can i achieve it using nPath routing or iRule or any ohter workaround solution..?

     

    • Lucas_Thompson_'s avatar
      Lucas_Thompson_
      Historic F5 Account
      Jun 25, 2015
      No irules are necessary. You must simply disable SNAT. When BIG-IP receives a connection, the source address is translated (or not) depending on those settings. The GUI path is: Local Traffic => Virtual Servers => (your smtp virtual) => Source Address Translation none means "don't NAT source address"
  • siru_129409's avatar
    siru_129409
    Icon for Nimbostratus rankNimbostratus
    Jun 25, 2015

    Hi Amolari, Actually i dont want to change my network settings, can i achieve it using nPath routing or iRule or any ohter workaround solution..?

     

    • Ronald_van_der3's avatar
      Ronald_van_der3
      Icon for Nimbostratus rankNimbostratus
      Jun 25, 2015
      It is hard to retain the original source IP if you cannot disable SNAT. Disabling SNAT means the return traffic should also pass through the F5, which is usually a change in network design.
  • MVA's avatar
    MVA
    Icon for Nimbostratus rankNimbostratus
    Jun 25, 2015

    We used GTM instead and it works great for our Exchange SMTP.