Exchange CAS terminating 80/443/25/143/993 and 587

Hello ,

We have two Exchange CAS servers that are load balanced by the F5 3600 LTM . The main function of these servers is for Outlook Web Access / Outlook Anywhere . In addition these servers are also used for SMTP , IMAP , Secure IMAP . We are currently not offloading SSL on the F5 . Initially I created two virtual servers one for HTTP and one for HTTPs . I added a redirect rule for HTTP . OWA and Outlook Anywhere portions work perfectly .

I created pools for SMTP , IMAP and Secure IMAP ( 993) and used the irule shown below to redirect traffic to the correct pool based on the destination port . This seems to work ok but I do not see the statistics on the pool increment when i establish a successful connection on port 25 .

When we started getting complaints about IMAP /25 not working , I created new virtual servers for each service ie SMTP, IMAP etc and assigned them to the corresponding pools . The behaviour was the same as it was when I was using the irule , i could see the statistics on the Virtual servers increment but not on the pools. The

The iRule I used is as below :

when CLIENT_ACCEPTED {

switch [TCP::local_port] {

25 { pool EXCAS_25}

443 { pool OWA_SSL_POOL}

143 { pool EXCAS_143}

587 { pool EXCAS_587}

993 { pool EXCAS_993}

}

}

I would appreciate any help in resolving this matter as I am very new to the F5. The error message on the client that uses IMAP is as below:

Error,Monday, February 18, 2013 5:11:01 PM,Quiksoft.EasyMail.SSL.SSLConnectionException: Error connecting to server. exchange.company.com ---> Quiksoft.EasyMail.SSL.SSLConnectionException: Error performing Handshake. Conn ---> System.Net.Sockets.SocketException: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond

OR

Error,Monday, February 18, 2013 5:08:03 PM,Process Name: Email Monitoring Model: Primary Model Component Name: Get All Messages Component Class Name: LogicBase.Components.IMAP4.IMAP4GetComponent Component ID: c3662797-48f2-11e1-a9da-005056a57db0 Exception Class Name: Quiksoft.EasyMail.SSL.SSLConnectionException Message: Error connecting to exchange.company.com Stack Trace: Quiksoft.EasyMail.SSL.SSLConnectionException: Error connecting to server. exchange.company.com ---> Quiksoft.EasyMail.SSL.SSLConnectionException: Error performing Handshake. Conn ---> System.Net.Sockets.SocketException: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond at Quiksoft.EasyMail.SSL.Internal.ᜐ.ᜏ(Exception A_0) at Quiksoft.EasyMail.SSL.Internal.ᜐ.ᜀ(ᜂ A_0, Byte[] A_1) at Quiksoft.EasyMail.SSL.Internal.ᜐ.ᜡ(EndPoint A_0) --- End of inner exception stack trace -

Thanks,

Karthik