# Quick commands

### Change owner of folder

```bash
sudo chown -R <linuxuser>:<linuxgroup> <pathtofolder>
```

### Manage Linux groups

#### Create group

```
groupadd <groupname>
```

#### Add user to group

```bash
usermod -a -G <linuxgroupname> <linuxusername>
```

#### List groups

```
sudo groups -la
```

### Managing tar files

#### Preview content of tar file

```bash
tar -tzf <pathtofile.tar>
```

#### Extract content of tar file

```bash
tar -xzf <pathtofile.tar>
```

### Copy files and folders

```bash
cp -r <sourcefolder1/sourcefile1> <sourcefolder2/sourcefile2> <sourcefolder3/sourcefile3> <destinationfolder>
```

### SCP

```bash
scp <username>@<sourcehost>:<sourcefile/sourcefolder> <destinationfolder>
```

### Get folder size

```bash
du -s <folderpath>
```

### Get task manager view

```
SAR
```

```
TOP
```

### Move foreground job to background

CTRL + Z

bg -&gt; Move job to background  
fg -&gt; Move job to foreground

### Generate SSH key

```bash
ssh-keygen -t rsa -b 4096 -C "<nameforsshkey>" -f .ssh/<nameforsshkey>
```

### Apt remove insecure repositories

```bash
sudo apt autoremove
```

### Replace characters in file

```
sed -i 's/<oldcharacters>/<newcharacters>/g' <filepath>
```

### Sync clock

```bash
sudo hwclock -s
```

## Resolve DNS Server

### Set dns server on specific interface

```
sudo systemd-resolve --set-dns=<yourprefereddnsip> --interface=<yourinterface>
```