Install SSL for ISPConfig Control Panel
To add SSL for ISPConfig control panel, add the server hostname as a website in ISPConfig and enable the LetsEnrypt checkbox. You…
Linux
VestaCP SSL for mail server
VestaCP install self signed SSL for mail server by default. To install valid SSL, login to VestCP, go to sites. You will…
Disable Native Notification on Google Chrome Ubuntu
On Ubuntu, Google chrome had a disable native notification option. On Chrome 78, this option is removed. But you still can manually…
apropos
apropos is a linux command that search manual pages and descriptions. Example root@mil-146068:~# apropos vagrant vagrant (1) – Tool for building and…
bind
bind is a DNS server. To check bind configuration for errors, run named-checkconf -z /etc/named.conf if chroot named-checkconf -z -t /var/named/chroot /etc/named.conf…
maximum number of open files and file descriptors in linux
To see open files in linux use the command lsof There is a limit set in the kernel on how many open…
lighttpd too many open files
lighttpd server crashes with fllowing error in error_log file. 2019-11-05 09:39:02: (network_linux_sendfile.c.143) open failed: Too many open files 2019-11-05 09:39:02: (connections.c.603) connection…
df not showing all mounts
On a server, df not showing all mounts root@server20 [~]# df -h Filesystem Size Used Avail Use% Mounted on tmpfs 3.9G 0…
Show disk usage with df
df command shows partitions and disks used by each partition. root@server54 [~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/sda2…
RHCSA Study Guide
1. Logical volume ‘home’ as created and mounted. Reduce its size to ‘192M’ (size from 185M to 200MB is acceptable) # lvdispaly…
debconf: unable to initialize frontend: Dialog
When installing a program in Ubuntu 18.04 server minimal installation, i get following error debconf: unable to initialize frontend: Dialog debconf: (No…
Install Unbound DNS caching server
Unbound is an Open source DNS caching and recursive resolver. You can find more about unbound at https://nlnetlabs.nl/projects/unbound/about/ To install unbound on…