topic Re: Sendmail - [Errno 101] Network is unreachable while sending mail in Splunk Search

Sendmail - [Errno 101] Network is unreachable while sending mail

clementros — Wed, 20 Mar 2019 09:22:07 GMT

I'm trying to use sendmail command with the gmail smtp server.

I use the "Search & Reporting" App to apply the following search:

index=nbtktfed sourcetype="nbtktfed.err" status=ERROR 
| stats count
| sendemail server="smtp.gmail.com:465" to="ros.clement@gmail.com" sendresults=true subject="Test mail" message="This message is send with the sendmail command of splunk" use_tls=true

This command return the following error in GUI :

command="sendemail", [Errno 101] Network is unreachable while sending mail to: ros.clement@gmail.com

My serveur is able to ping the "smtp.gmail.com" server. But when i tried to execute a telnet this return "Network is unreachable".

Here is my Server setting > Email settings configuration :

Re: Sendmail - [Errno 101] Network is unreachable while sending mail

nickhills — Wed, 20 Mar 2019 10:05:05 GMT

Are you certain there are no firewalls (local or network) preventing traffic leaving your network on the mail port?

If you are in an enterprise, its quite common for outbound email ports to be blocked

Re: Sendmail - [Errno 101] Network is unreachable while sending mail

clementros — Wed, 20 Mar 2019 10:26:38 GMT

HI @nickhillscpl,

I have a virtual machine (CentOS 7) wich i'm sure the firewalld service is stop and disable.

On this VM i have a docker container (Debian 9) with splunk entreprise. When i run the command "iptables -L" debian say "iptables command not found".

Is there another firewall on Debian 9 ?

If outbound email ports are blocked, how can i test sendmail on local ?

Re: Sendmail - [Errno 101] Network is unreachable while sending mail

nickhills — Wed, 20 Mar 2019 10:32:59 GMT

I would start with your network/comms team - if you have perimeter firewalls blocking ports, they will likely have to make the changes to allow your traffic to flow.

I think debian uses firewalld, but I'm more of an RHEL guy!