Failover to another IP
Question asked by Terry Reynolds - 5/20/2021 at 5:34 AM
I have 5 IP's on my server that I transferred from one host to a VM on another.  I can send and receive email from the server.  The mail server is mail.domain.com on IP xxx.xxx.xxx.188 and resolves externally to this as does the PTR record, yet there are loads of bounce-backs.  When I look at a received email header I see it has used xxx.xxx.xxx.186.  No protocols are actually bound to this IP and it is used (or meant to be) by HTTP(S) traffic.
When I look in the Smartermail logs I see the following;

  • Initiating connection to
  • Connecting to (Id: 1)
  • Exception connecting to (Id: 1)
  • System.Net.Sockets.SocketException (0x80004005): The requested address is not valid in its context
  • Binding to local ip 'xxx.xxx.xxx.188' failed.  Switched binding to primary local ip.
Being on a VM I think it's failing over to the server IP ( which does have protocol bindings and is then simply sending out on xxx.xxx.xxx.186.

I think my first question is, why does it fail to bind to 188?
Second question, if I can't stop the error, how do I then force the internal IP to use 188?

I hope the above makes sense and would dearly like to know how to resolve this.


4 Replies

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Terry Reynolds Replied
Does anyone have any ideas please?
You need to open a ticket and probabily the tecnicians need to look at you VM network configurations.

I think there's something wrong with  your SmarterMail config AND with the network config of your VM, but without accessing it directly and see it I cannot help you...

Gabriele Maoret - Head of SysAdmins at SERSIS Currently manages 6 SmarterMail installations (1 in the cloud for SERSIS which provides services to a few hundred third-party email domains + 5 on-premise for customers who prefer to have their mail server in-house)
Terry Reynolds Replied
Thanks for the response Gabriele.  

As an interim measure I have asked the host to add an additional PTR for the second IP address and once the bounce backs cease will open it then.

Ron Raley Replied
I believe that your IP address MUST be binded with the SMTP SmarterMail protocol.  Also, you likely need to change your PRIMARY IP for the Network Adapter using ipconfig.

This is my best guess.  Good luck!

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