Docker container can't send Email.

[Kris33]

As said in title.

Error message is :

Unable to send email. Verify your email server settings. For details, refer to the error (Mail server connection failed; nested exception is com.sun.mail.util.MailConnectException: Couldn't connect to host, port: mymailserver.com, 587; timeout 10000;\n nested exception is:\n\tjava.net.NoRouteToHostException: No route to host (Host unreachable). Failed messages: com.sun.mail.util.MailConnectException: Couldn't connect to host, port: mymailserver.com, 587; timeout 10000;\n nested exception is:\n\tjava.net.NoRouteToHostException: No route to host (Host unreachable)) stack trace in os.log file."

Other than that lims works well no other issue.

[Kris33]

Host is almalinux . I attempted disabling selinux and firewalld but to no avail.
container doesn't seem to have network tools installed to debug the issue. although in openspeciment I tried using mailserver FQDN, mailserver IP and port 25, 465,587 with startls enabled or disabled.

[todiap]

have you found any solution? i have the same problem. ubuntu 20

[aleksandrsa]

Dealing with the same issue. It appears to be related to restrictions in the wider deployment environment. E.g., Docker containter is not allowed to access wider network and special actions from IT department are required to allow that.

E-mail sending works fine in a local environment (e.g., Docker on personal machine).

Docker containter, indeed, doesn't have network tools. To solve this, use another repository https://github.com/bibbox/img-openspecimen . There, you can modify the Dockrefile to install more tools for diagnostics from within the app container. For example:

## INSTALL DEPENDENCIES
# apt install
RUN apt install -y -q openjdk-17-jdk-headless \
    && apt install -y -q openjdk-17-jre-headless \
    && apt-get install -y -q tomcat9 \
    && apt-get install -y -q nano \
    && apt-get install -y -q wget \
    && apt-get install -y mysql-client \
    && apt-get install -y -q telnet \
    && apt-get install -y -q net-tools \
    && apt-get install -y -q dnsutils \
    && apt-get install -y -q iputils-ping \
    && apt-get install -y -q iproute2 \
    && apt-get update -y -q

It is also a good idea to test if the host machine itself can establish connection with a mail server. For example, by using telnet.