Re-add disk to array:
mdadm --manage /dev/mdx --add /dev/sdx1
Assemble Array
sudo mdadm --assemble --scan
Stop Array
sudo mdadm -S /dev/mdx
Create Array
sudo mdadm --create --verbose /dev/mdx --level=0-6 --raid-devices=3 /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1
Linux RAID Filesystem
gdisk partition type:
Hex Code: 42 ‘Linux Raid’
Mount Windows Share in Linux
sudo mount -t cifs -o username=<win_share_user> //WIN_SHARE_IP/<share_name> /mnt/win_share
Requirements: sudo yum -y install cifs-utilsLetsEncrypt + Certbot + Subdomain
sudo certbot certonly –apache -d x.example.com
Certbot
Certbot always puts the latest version of all certificates under /etc/letsencrypt/live:
/etc/letsencrypt/live
├── mail.example.org
│ ├── cert.pem -> ../../archive/mail.example.org/cert8.pem
│ ├── chain.pem -> ../../archive/mail.example.org/chain8.pem
│ ├── fullchain.pem -> ../../archive/mail.example.org/fullchain8.pem
│ └── privkey.pem -> ../../archive/mail.example.org/privkey8.pem
└── www.example.org
├── cert.pem -> ../../archive/www.example.org/cert7.pem
├── chain.pem -> ../../archive/www.example.org/chain7.pem
├── fullchain.pem -> ../../archive/www.example.org/fullchain7.pem
└── privkey.pem -> ../../archive/www.example.org/privkey7.pem
Therefore you would configure services like this:
SSLCertificateFile /etc/letsencrypt/live/www.example.org/fullchain.pem
SSLCertificateKeyFile /etc/letsencrypt/live/www.example.org/privkey.pem
This way, services only need to be reloaded, not reconfigured, after every renew. Use certbot’s “deploy hook” feature to automate permission changes, service reloads, and anything else that needs automating.
Flush Linux DNS Cache
$ sudo systemd-resolve --flush-caches
$ sudo resolvectl flush-cachesDefault Files/Folders *Nix Permissions
There is no magic procedure, the only way to restore it would be manually.
Fortunatelly the procedure is easy, but it should have to be performed carefully
Step 1: Copy the following script, paste it on your console to generate fixpermission script
echo ‘ chmod -R 755 /bin /boot /dev /etc/ /home /lib /lib64 \ /media /mnt /opt /run /sbin /srv /usr /var
chmod -R 777 /initrd.img /vmlinuz chmod -R 1777 /tmp chmod -R 555 /sys chmod -R 555 /proc chmod -R 700 /root
‘ > fixpermission
chmod +x fixpermission
./fixpermission
The above will create a script named fixpermission and run it by ./fixpermission if not already invoked.
Step 2: Run stat -c ‘%A %a %n’ /* to show your proper directory and their permission as restored.
Example: Your directory permission structure should look similar to the following:
drwxr-xr-x 755 /bin
drwxr-xr-x 755 /boot
drwxr-xr-x 755 /dev
drwxr-xr-x 755 /etc
drwxr-xr-x 755 /home
lrwxrwxrwx 777 /initrd.img
lrwxrwxrwx 777 /initrd.img.old
drwxr-xr-x 755 /lib
drwxr-xr-x 755 /lib64
drwx------ 700 /lost+found
drwxr-xr-x 755 /media
drwxr-xr-x 755 /mnt
drwxr-xr-x 755 /opt
dr-xr-xr-x 555 /proc
drwx------ 700 /root
drwxr-xr-x 755 /run
drwxr-xr-x 755 /sbin
drwxr-xr-x 755 /srv
dr-xr-xr-x 555 /sys
drwxrwxrwt 1777 /tmp
drwxr-xr-x 755 /usr
drwxr-xr-x 755 /var
lrwxrwxrwx 777 /vmlinuz
lrwxrwxrwx 777 /vmlinuz.oldLinux Printer Installation
Start Gear (upper right corner) => System settings => Printer => Add button
The 2280 was not an option, so I recommend downloading and installing the driver per the OEM. Driver install instructions:
Invoke the installation script: not the model number is appended as an argument.
sudo bash linux-brprinter-installer-2.2.1-1 HL-2280D
When faced with selecting the connection type and its configuration: the printer is network (LAN) configured so I selected the IP address option.
Will you specify the Device URI? [Y/n] ->Y
Select option 11 => specify IP address
Type in the address and script will prompt to print test page
Ring the bell and increment the counter if you were successful with setting up your printer.
SMS.
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