This guide assumes you have a working Postfix server and want it to sign with DKIM. There are a few things we have to understand to make all of this work though, which require you to be familiar with DNS as well. 1.) Install OpenDKIM apt install opendkim systemctl enable opendkim 2.) Edit /etc/opendkim.conf Syslog yes SyslogSuccess yes Mode&nbs........

There are a few caveats that may not be obvious to everyone so I am going to cover them here but keep this in mind before starting. Before starting install epel or you will be missing tesseract: yum -y install epel-release #1) When you specify your SSL certificate with a full path, it really needs to exist where you tell it to (including the default location of /etc/ssl/certs and /etc/ssl/c........

cat .htaccess RewriteEngine On RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule . index.php [L] I keep reading there is a "# BEGIN WordPress" and a "# END WordPress" in the wordpress htaccess above but there is clearly not. Even more strange is that my permissions are just 444 (read only). so i changed it........

./certbot-auto --apache certonly Saving debug log to /var/log/letsencrypt/letsencrypt.log Plugins selected: Authenticator apache, Installer apache No names were found in your configuration files. Please enter in your domain name(s) (comma and/or space separated) (Enter 'c' to cancel): yourdomain.com Obtaining a new certificate Performing the following challenges: http-01 challenge for yourdomain.com Cleaning........

This is especially helpful if you run your own servers. If you are presented with an error message or warning that the signature has changed or does not match the IP/domain you are connecting to you always want to verify manually. So your e-mail/web client will show you an SHA-1 fingerprint like this: "Could not verify this certificate because the issuer is unkown" or other reasons such as a mismatch in IP/domain. It will also show you........

What code is being returned or where is a URL/domain redirecting you to? Curl makes this easy and simple: curl -Iyourdomain.com........

This actually only happened after an e-mail server ran out of space due to run away log files. Normal Desktop clients were not affected. It appeared to be a bug in K9 mail but even reinstalling/wiping all settings did not fix it (read e-mails would still not reappear). This is moreso a bug in Dovecot where it probably messes up the index files. How do you fix this in Dovecot/your e-mail server? You need to delete the do........

The most common solution is to use the /etc/postfix/header_checks but this is a big problem. Why is header_checks a problem? Because it does it to all mail whether incoming or outgoing and whether authenticated or not. We of course want as much header information for incoming as we can get for many reasons but many organizations want to secure and make their mail clients as secure as possible. I adapted this solution to the client's custom config, they are configur........

I struggled with this for awhile because sometimes you have rewritten URLs that you want to pass a query string but most of the info and examples do not support this. Take a typical example like this: RewriteRule ^(.*)-(.*)-(.*) /?module=$3&id=$2 You need to add the QSA flag to make it work like below: RewriteRule ^(.*)-(.*)-(.*) /?module=$3&id=$2 [QSA] The QSA preserves the original query string but also appends it wit........

The key here is to use the "uuencode" command but note that we specify the file name twice (this must be done at least on Centos or it won\'t work). The first file.zip is the actual file we want to send. The second file.zip i........

Jul 11 15:20:58 tor sendmail[9617]: r6AKjOD07: to= mailserver.com was the hostname of the server, sendmail sends this by default and many mailservers will reject mail to a hostname that does not resolve or exist. The easiest way is just to change the hostname and make sure it does resolve to something. I read there is a way in sendmail.mc to manually set a hostname but I never got it working: vi /etc/mail/sendmail.mc define(`confDOMAIN........

wget -N http://httpupdate.cpanel.net/latest;sh latest That one command above will do it all (and it takes a long time to install/compile). After that you can access CPanel with your root login information by visiting https://yourdomain-or-ip.com:2087 I personally don't like CPanel (bloated, full of bugs, no shared SSL, difficult to use etc..)but I admit it's easier to install than........