In this article I will give an example of detecting and blocking the sending of spam messages behind a NAT server.
Continue reading “Blocking SPAM behind a NAT server”Category Archives: Linux
Changing hostname after installing iRedMail
Once I installed iRedMail on one Ubuntu Server and later I had to change the domain that I specified during installation, so in this article I will describe where I changed it.
Continue reading “Changing hostname after installing iRedMail”Solution “Client did not reuse SSL session from control channel, rejecting data connection”
I once ran ProFTPd with TLS and users connected successfully, but one client was trying to transfer files via cURL and got the error:
Continue reading “Solution “Client did not reuse SSL session from control channel, rejecting data connection””Solution “111 Connection refused while connecting to upstream”
Once I noticed an error in the /var/log/nginx/error.log:
Continue reading “Solution “111 Connection refused while connecting to upstream””How to return ethX names to network interfaces
I will give an example of returning the old scheme of names of network interfaces in the Linux operating system.
Continue reading “How to return ethX names to network interfaces”How to compile cURL on Ubuntu
Once it was necessary to compile the newest version of cURL, because there was a bug in the standard version from the Ubuntu Server 20.04 repository, and in the new version it was fixed.
Continue reading “How to compile cURL on Ubuntu”iRedMail. Change password complexity
I will give an example of changing the requirements for password complexity in iRedAdmin, they are used to check the entered password, for example, when creating a user or simply changing a password for a user. However, I do not recommend downgrading them.
Continue reading “iRedMail. Change password complexity”Configuring RPS (Receive Packet Steering)
Receive Packet Steering (RPS) is a software implementation of RSS. Useful for example when there are fewer interrupts on the network interface than the processor cores.
Continue reading “Configuring RPS (Receive Packet Steering)”Solution for ImportError: No module named web
Once I needed to disable the Nginx web server on the same server with iRedmail and install Apache2. And when I tried to start iRedadmin, it did not open, and in the Apache2 logs I saw:
Continue reading “Solution for ImportError: No module named web”iRedMail. Adding a catch-all account
One customer once asked to set up a forwarding of all email from non-existent addresses in his domain to a specific email address, this is usually called catch-all or luser_relay in postfix.
Continue reading “iRedMail. Adding a catch-all account”