I try to reverse proxy all the incoming email traffic to asolution in my debian server via haproxy:The haproxy.cfg configuration is: globallog /dev/log local0log /dev/log local1 noticechroot /var/lib/haproxystats socket /run/haproxy/admin.sock mode 660 level adminstats timeout 30suser haproxygroup haproxydaemon# Default SSL material locationsca-base /etc/ssl/certscrt-base /etc/ssl/private# Default ciphers to use on SSL-enabled listening sockets.# For more information, see ciphers(1SSL).
Check Imap Proxy Is Active Windows 10
This article will explain how to configure NGINX Plus or NGINX Open Source as a proxy for a mail server or an external mail service. IntroductionNGINX can proxy IMAP, POP3 and SMTP protocols to one of the upstream mail servers that host mail accounts and thus can be used as a single endpoint for email clients. This may bring in a number of benefits, such as:. easy scaling the number of mail servers.
choosing a mail server basing on different rules, for example, choosing the nearest server basing on a client’s IP address. distributing the load among mail serversPrerequisites.NGINX Plus (already includes the Mail modules necessary to proxy email traffic) or NGINX Open Source compiled the Mail modules using the -with-mail parameter for email proxy functionality and -with-mailsslmodule parameter for SSL/TLS support.
Recently I ran into an issue configuring some new Exchange 2013 servers for IMAP4. I'll share my configuration, troubleshooting steps and the solution here in this article.Enabled and started the IMAP4 and IMAP4BE services and created a virtual service on the load balancer listening on port 993. I've done this many times before and was quite surprised that the initial testing with Outlook in IMAP4 mode failed. From a testing perspective I prefer Outlook because it allows not only connecting, but also authentication and actually accessing a mailbox through IMAP4.I proceeded with a telnet to the load balancer VIP on port 993 and got nothing more than a black screen.
Not exactly sure what to expect on port 993 because the encryption I tested port 143 directly against the server, bypassing the load balancer. Here I expected the IMAP banner but saw again just an empty window.Blank screen, hitting any key resulted in the PowerShell prompt gain.
Telnet on the local server to localhost instead of the server name:So a telnet to localhost results in the IMAP banner, all other options fail. Time to look under the hood and consult Managed Availability. Get-HealthReport reported the Health Set IMAP.Proxy in an offline state:Setting the state back to active did the trick:Set-ServerComponentState -Identity ex01 -Component ImapProxy -State Active -Requester HealthAPIWith all components in an active state I was able to connect with IMAP with both telnet and Outlook.I have seen this issue on multiple servers now, happened to be all running CU7.
On the other hand, some other servers did not have this issue. If you run into issues trying to get IMAP4 working on Exchange 2013, maybe the information above helps you to find the cause.
IMAP4 is a mail protocol that allows users to be disconnected from the main messaging system and still be able to process mail. Users can store messages on a local machine or on a server.IMAP4 protocol can work over two types of connection: in clear (called IMAP, default port 143) or over TLS (called IMAPs, default port 993). Hence, you can choose a variety of deployment types:.TCP forward on IMAP (TCP/143) only.TCP forward on IMAPs (TCP/993) only.SSL offload on IMAPs (TCP/993) only.TCP forward on both IMAP (TCP/143) and IMAPs (TCP/993).TCP forward on IMAP (TCP/143) and SSL offload on IMAPs (TCP/993). NoteSSL offload means that HAProxy terminates the SSL/TLS connection and deciphers the traffic. It is not compatible with STARTTLS where the connection starts as clear and then switches to TLS. To be compatible with STARTTLS, use the TCP forward configuration.The configuration template below introduces HAProxy configuration for MS Exchange 2010 IMAP service in TCP forward on both IMAP (TCP/143) and IMAPs (TCP/993) layouts.You may have to modify these parameters to suit your environment: bindThe listening IP (usually an IP address configured over VRRP) serverThe server name and IP addresses.
NoteYou can use the default XCHANGE2010TCP section for other Exchange 2010 TCP based services. There is no need to duplicate it.