Posts tagged with “sysadmin”

Unauthenticated email from [DOMAIN] is not accepted due to 550-5.7.26 domain's DMARC policy.

Written by Simone

I was enabling Exim on my IONOS VPS to deliver email through a smarthost and encountered the error message in this post's title (unable to send to Gmail users.. It's always them!)

After fiddling a while with DMARK and SPF I reconfigured Exim itself to rewrite sender address, so that emails coming from "spacenest.it" (IONOS domain) were sent as coming from "woodpeckersnest.eu", the smarthost and real email server.

Everything is done via this command:

# dpkg-reconfigure exim4-config

And the resulting configuration in /etc/exim4/update-exim4.conf is:

dc_eximconfig_configtype='smarthost'
dc_other_hostnames='cassandra.spacenest.it;spacenest.it'
dc_local_interfaces='127.0.0.1'
dc_readhost='woodpeckersnest.eu'
dc_relay_domains=''
dc_minimaldns='false'
dc_relay_nets=''
dc_smarthost='pandora.woodpeckersnest.space::587'
CFILEMODE='644'
dc_use_split_config='false'
dc_hide_mailname='true'
dc_mailname_in_oh='true'
dc_localdelivery='mail_spool'

On OVH's postfix I just had to modify this line in /etc/postfix/main.cf:

mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128 94.143.138.27/32

where that last IP is the IP Address of my IONOS server.

Awesome Selfhosted

Written by Simone

This is where I found the idea for a blog with chyrp-lite. That repo is full of awesomeness 😎

Process Keepalive

Written by Simone

Scope: restart a process if it exited for any reason

To do: edit "process-restart.sh" substituting "process" with the actual process name and startup command/path. Moreover you'd want to rename both file with the process name. To find what the actual process name is, do a ps aux | grep <name> and then test with pgrep -f <process_you_found> - see if it returns the correct PID.

Usage: run ./process-loop.sh

TIP: always use TMUX or screen.

I'm using this method to keep my bots¹ and the ETS2 server always running:

¹ BOTS == ZED, a couple XMPP bots, Simplebot Mastodon etc..

File attachment:

process-keepalive.zip (0.5 KB)