bash – check if a string in a variable
if you use#! /bin/zsh $MYVAR=”Hello world” if [[ $MYVAR == *”hello”*]] thenecho “FOUND”fi If we don’t use #! /bin/zsh $MYVAR=”Hello world”if [[ $MYVAR == *”hello”*]]; thenecho “FOUND”fi
Virtualbox: can’t remove / attach new hard disk
When i try to remove a disk in Virtualbox with this command: I got the following error And the fix is:
DNS: Why i can’t create txt record for sub domain?
Please check if your subdomain is a CNAME , the DNS rule does not allow CNAME record to have other record. The fix is to use A record for...
cricket – rrdcached: some info in mind
rrdcached is a daemon that receives updates to existing RRD files, accumulates them and, if enough have been received or a defined time has passed, writes the updates to...
A detailed page about PHP thread.
### A Detailed Page About PHP Threads: Understanding Multithreading in PHP PHP is one of the most widely used server-side programming languages, primarily known for its ability to generate...
Mysql import from 5.6 to 5.7 : Column count of mysql.user is wrong. Expected 42, found 44. The table is probably corrupted
You might receive the error Column count of is wrong. Expected 42, found 44. The table is probably corrupted , this is probably because you import the whole...
apt-get add new data source
When we add new data: # vi /etc/ ... deb stretch main contrib non-free deb-src stretch main contrib non-free we got some errors below: # apt-get update...
Samsung J7 dead after not using for long time.
I had a samsung J7, it’s in the drawer for many months. today i tried to charge it, there was no sign it’s charging. i changed many cables ,...
How to read rrd file?
rrdtool dump rrdtool info rrdtool graph /dev/null -s 3600 DEF:ierr=:ds1:AVERAGE VDEF:ioct_a=ierr,AVERAGE PRINT:ierr:%lf this command will get the avg value of ds1 (ds1 is the dataset –...
Ubuntu 18.04 : how to run start up script
Create a service: sudo vi /etc/systemd/ Add your code there: Description=/ Compatibility ConditionPathExists=/ Type=forking ExecStart=/ start TimeoutSec=0 StandardOutput=tty RemainAfterExit=yes SysVStartPriority=99 WantedBy= Create and make sure / is executable...