- edited description
Cannot mail from google compute server using monit v5.22 and sendgrid
1 Create VM in Google Compute
2 Compile and Install monit v5.22 on centos-release-6-6.el6.centos.12.2.x86_64 server
3 Add following to /etc/monitrc
set mailserver smtp.sendgrid.net port 2525 username "apikey" password "<key>" using TLSV1 with timeout 30 seconds
4 Start monit
5 Following errors seen in /var/log/monit.log
[UTC Jun 6 08:34:32] error : Cannot create socket to [smtp.sendgrid.net]:2525 -- SSL connection error: error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol
[UTC Jun 6 08:34:32] error : Cannot open a connection to the mailserver smtp.sendgrid.net:2525 -- Success
[UTC Jun 6 08:34:32] error : Mail: Delivery failed -- no mail server is available
[UTC Jun 6 08:34:32] error : Aborting event
-
I used nc command to check port is open
-
I confirmed with Google that port 2525 should be used for outbound smtp
Comments (7)
-
reporter -
reporter - edited description
-
reporter - edited description
-
reporter - edited description
-
repo owner The "using TLSv1" option forces the communication to TLSv1 (connection with SSL handshake), but the "smtp.sendgrid.net" is not SSL/TLS port ... it provides plaintext SMTP service and the client can use STARTTLS to switch to SSL, so the SSL connection ends up with "SSL23_GET_SERVER_HELLO:unknown protocol" (the server doesn't speak SSL):
$ telnet smtp.sendgrid.net 2525 Trying 159.122.224.196... Connected to smtp.sendgrid.net. Escape character is '^]'. 220 SG ESMTP service ready at ismtpd0004p1lon1.sendgrid.net
The "using TLSv1" option should be removed from monit configuration.
-
repo owner - changed status to closed
-
reporter changed configuration as follows:
set mailserver smtp.sendgrid.net port 2525 username "apikey" password "<key>" using STARTTLS with timeout 30 seconds
It works
Issue can be closed. Please excuse my silliness
- Log in to comment