Enable Passive FTP in ISPConfig

To enable Passive FTP in Debian/Ubuntu installation of ISPConfig, run

Restart pure-ftpd

Now open ports 40110-40210 in firewall.

On CSF Firewall, edit


At ened of TCP_IN line.


See ispconfig

Reorder windows in tmux

To reorder windows in tmux, you can use following command

Press CTRL + B or whatever prefix you use, then press . (dot). This will ask you number/position where you need current window moved.

Another method is

This will give you tmux command promt. Now enter

This will move current window to position 0. This only work if position 0 is empty. If another window already present in position 0, use swap-window command.

This with swap current window with window in position 0.

Another useful command is

This will allow you to rename current tmux window.

Using shortcuts

You can edit .tmux.conf file and add following

Now you can use CTRL + SHIFT + LEFT OR RIGHT arrow to move windows.

See tmux

Setup Tor Hidden Service on CentOS 7

Tor is provided by EPEL repository on CentOS 7. Install EPEL repo with command

Install tor

Edit tor config file

Uncomment or add following lines

Restart tor with command

Now your tor hidden service is ready to use. You need to run your web application on

To see URL of your tor hidden service, run

Make sure to make a backup of folder “/var/lib/tor/hidden_service/” as it comtains keys for this .onion domain. If you lost it, you will lose your domain name. So it is very important you keep the files safe.

To stop/start tor, run

See tor

tor browser

Tor Hidden Service in Ubuntu/Debian

tor browser

To install tor on Ubuntu/Debian, run

Default configuration file for tor is /etc/tor/torrc

To enable hidden service, edit /etc/tor/torrc

uncomment lines

Create folder for your hidden service

You need to install Apache/Nginx etc.. to serve your web application. Make sure to configure web application listen on

Now restart tor with command

Ubuntu/Debian support multiple instances of tor. You can use command “/usr/sbin/tor-instance-create” to create new tor instance. Configuration for instanced tor available at /etc/tor/instances/INSTANCE_NAME/torrc

To see URL for your Hidden service, run


You should be able to visit the application using .onion link in Tor Browser.

You need to take backup of tor folder (/var/lib/tor/hidden_service) as it contains your secret keys, this is needed to use the .onion domain name. If you lose this, you will lose the .onion url.

To start the service on boot, run

See Tor


Proxmox 6 disable No valid subscription notice

To disable No valid subscription notice from proxmox, edit file


This is on line 380. inside function checked_command

Replace with

Resart pveproxy

Zimbra webmail not working on port 80/443

On Zimbra mail server, webmail stopped working on Port 80/443. Admin interface worked properly on url https://hostname:7071/. There is no errors displayed under monitor tab of Zimbra Admin.

To fix, run

After running this, netstat -lntp start showing nginx running on port 80 and 443

virt-manager kvm


virt-manager is a GUI tool to manage virtual machines.

On CentOS desktop, install it with

For installing on Ubuntu, see Install virt-manager on Ubuntu

Connect to remote KVM server

To connect to remote KVM server from virt-manager, Go to File > Add Connection

virt-manager kvm

If SSH port is not 22, use IP:PORT format to connect to KVM installation.

Once connected, you will see all VMs. Here we have 1 VM with name “foo”

You can double click on a VM to access its console/desktop.

virt-manager console

See kvm