---
title: Sendmail
description: Follow the guide below to configure Sendmail to use SocketLabs as the Smart Host and Internet Mail Relay
---
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# Sendmail
## Follow the guide below to configure Sendmail to use SocketLabs as the Smart Host and Internet Mail Relay
- Login to your server via SSH
- Sudo to superuser
- Navigate to your Sendmail configuration directory. This config file is typically found at /etc/mail. We recommend making backups of each configuration file before making changes.
```
sudo sucd /etc/mailmv sendmail.mc sendmail_backup.mc
```
- Edit Sendmail configuration file **/etc/mail/sendmail.mc u**sing a file editor such as ‘nano’ to add the below code after #dnl define('SMART\_HOST', 'smtp.your.provider')dnl.
```
nano sendmail.mc
```
> /etc/mail/sendmail.mc
>
> define('SMART\_HOST', 'smtp.socketlabs.com')dnl
>
> FEATURE('authinfo')dnl
>
> define('RELAY\_MAILER\_ARGS', 'TCP $h 2525')dnl
Port 587 and 25 can also be used instead of 2525, if necessary.
- To add authorization credentials, edit the file ‘/etc/mail/authinfo’ using your editor and add the following line, replacing ‘SocketLabs\_SMTPusername’ and ‘SocketLabs\_SMTPpassword’ with your SMTP credentials provided in the Control Panel of your SocketLabs server.
```
nano authinfo
```
> /etc/mail/authinfo
>
> AuthInfo:smtp.socketlabs.com U:SocketLabs\_SMTPusername" "P:SocketLabs\_SMTPpassword"
- Update your configuration files
```
cd /etc/mailm4 sendmail.mc > sendmail.cfmakemap hash authinfo < authinfo
```
- Restart the Sendmail service
```
/etc/init.d/sendmail restart
```
or
```
service sendmail restart
```
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