Category: Linux

Linux User
November 27, 2020
Disable systemd-resolved on Ubuntu/Deb/CentOS
systemd-resolved provide DNS resolver facility in newer version of Linux servers running systemd.

I prefer manually editing /etc/resolv.conf and add resolvers. If you are running your own DNS server, then you need to disable systemd-resolved as it listen on port 53, with out disabling the service, you can’t start your DNS server.

To disable systemd-resolved, run
```
wget https://raw.githubusercontent.com/serverok/server-setup/master/tools/disable-systemd-resolved.sh
bash disable-systemd-resolved.sh
```
Or do the following.
```
systemctl disable systemd-resolved.service
systemctl stop systemd-resolved
```
Now create /etc/resolv.conf file
```
rm -f /etc/resolv.conf
tee /etc/resolv.conf << END
nameserver 8.8.8.8
nameserver 1.1.1.1
END
```
See resolv.conf, dns
November 27, 2020
Enable rc.local
To enable /etc/rc.local file run on system startup on servers runing systemd, you can run
```
systemctl enable rc-local
```
Now you need to create file /etc/rc.local with 755 permission.
```
touch /etc/rc.local
chmod 755 /etc/rc.local
```
See Autostart
November 26, 2020
proxychains
proxychains allow you to route traffic using proxy servers. This is useful for routing traffic throihg applications that do not support proxy by default. For example, i use ssh through proxy chains.

To install proxychains on Ubuntu, run
```
apt install -y proxychains
```
Now you need to edit /etc/proxychains.conf and add your proxy servers.
```
sudo vi /etc/proxychains.conf 
```
On my computer, i use SSH tunnel to a sevrer on port 7878, so i added following to end of my proxychains.conf
```
socks5  127.0.0.1  7878
```
To text proxy proxychains, run
```
boby@sok-01:~$ curl checkip.amazonaws.com
59.92.71.53
boby@sok-01:~$ proxychains curl checkip.amazonaws.com
ProxyChains-3.1 (http://proxychains.sf.net)
|DNS-request| checkip.amazonaws.com 
|S-chain|-<>-127.0.0.1:7878-<><>-4.2.2.2:53-<><>-OK
|DNS-response| checkip.amazonaws.com is 34.193.115.2
|S-chain|-<>-127.0.0.1:7878-<><>-34.193.115.2:80-<><>-OK
51.38.246.115
boby@sok-01:~$ 
```
As you can see when using proxychains, you get a difernt IP as traffic get routed through proxy server specified in proxychains.conf

Proxychains show some connection info, you can hide this by editing proxychains.conf and uncommenting the line
```
# Quiet mode (no output from library)
#quiet_mode
```
With quite mode enabled, you will see
```
boby@sok-01:~$ proxychains curl checkip.amazonaws.com
ProxyChains-3.1 (http://proxychains.sf.net)
51.38.246.115
boby@sok-01:~$ 
```
See Proxy
November 26, 2020
Server Load
Here are some useful commands to check server load.

iostat shows disk IO usage. %iowait shows how much time the process waits for disk operation. This should be 0. If you are on VPS, check for %steal to see if the host server is overloaded.
```
iostat 1 10
```
Checks for processes in ‘D’ state
```
for x in `seq 1 1 30`; do ps -eo state,pid,cmd | grep "^D"; echo "-"; sleep 2; done
```
Top processes using CPU resources
```
top -bn 1 | head -20
```
Check Running Process
```
ps aux
top
atop
pstree
```
Check For Bad Scripts

WPRobot plugin for wordpress take lot of cpu usage, find sites using WPRobot
```
find /home -name 'wprobot.php'
```
November 24, 2020

Requesting a zone trasnfer with dig

To request a zone transfer using dig, use

dig @NAME_SERVER_HERE  -t AXFR  DOMAIN_NAME_HERE

Example

[root@vps3 poweradmin]# dig @server10.hosthat.com  -t AXFR  bizhat.com

; <<>> DiG 9.5.1-P2-RedHat-9.5.1-2.P2.fc10 <<>> @server10.hosthat.com -t AXFR bizhat.com
; (1 server found)
;; global options:  printcmd
bizhat.com.             86400   IN      SOA     dns10.hosthat.com. hostonnet.gmail.com. 2008091126 7100 7200 2419100 86400
bizhat.com.             14400   IN      MX      0 server52.hosthat.com.
bizhat.com.             86400   IN      NS      dns10.hosthat.com.
bizhat.com.             86400   IN      NS      server70.hosthat.com.
bizhat.com.             14400   IN      A       67.228.96.44
*.bizhat.com.           14400   IN      A       66.90.101.78
aaj.bizhat.com.         14400   IN      A       67.228.37.136
adserver.bizhat.com.    14400   IN      A       174.37.154.236
advt.bizhat.com.        14400   IN      A       67.228.95.96
alappuzha.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
angamaly.bizhat.com.    14400   IN      CNAME   cms.bizhat.com.
arthunkal.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
astrology.bizhat.com.   14400   IN      A       67.228.37.136
austin.bizhat.com.      14400   IN      CNAME   cms.bizhat.com.
autos.bizhat.com.       14400   IN      CNAME   cms.bizhat.com.
bangalore.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
banner.bizhat.com.      14400   IN      A       67.228.37.136
bb.bizhat.com.          14400   IN      A       76.76.18.19
beauty.bizhat.com.      14400   IN      CNAME   cms.bizhat.com.
bizhat-radio.bizhat.com. 14400  IN      A       72.21.41.242
blog.bizhat.com.        14400   IN      A       76.76.18.23
*.blog.bizhat.com.      14400   IN      A       76.76.18.23
blogs.bizhat.com.       14400   IN      A       208.53.161.106
books.bizhat.com.       14400   IN      CNAME   cms.bizhat.com.
bsc.bizhat.com.         14400   IN      A       67.228.37.136
calendar.bizhat.com.    14400   IN      CNAME   cms.bizhat.com.
chat.bizhat.com.        14400   IN      A       67.228.37.136
chellanam.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
cherthala.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
cherthalainfo.bizhat.com. 14400 IN      CNAME   cms.bizhat.com.
classifieds.bizhat.com. 14400   IN      A       67.228.37.136
cms.bizhat.com.         14400   IN      A       76.76.18.22
computer.bizhat.com.    14400   IN      A       67.228.37.136
counter.bizhat.com.     14400   IN      A       76.76.18.19
dating.bizhat.com.      14400   IN      A       76.76.18.23
dileep.bizhat.com.      14400   IN      CNAME   cms.bizhat.com.
dir.bizhat.com.         14400   IN      A       72.36.166.222
directory.bizhat.com.   14400   IN      A       67.228.96.44
divyaunni.bizhat.com.   14400   IN      A       67.228.96.44
domainname.bizhat.com.  14400   IN      CNAME   cms.bizhat.com.
domains.bizhat.com.     14400   IN      A       67.228.37.136
downloads.bizhat.com.   14400   IN      A       67.228.95.96
ecards.bizhat.com.      14400   IN      A       67.228.37.136
education.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
emedia.bizhat.com.      14400   IN      A       67.228.37.136
ernakulam.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
ezhupunna.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
filmreviews.bizhat.com. 14400   IN      A       76.76.18.23
finance.bizhat.com.     14400   IN      CNAME   cms.bizhat.com.
findhost.bizhat.com.    14400   IN      A       67.228.37.136
forums.bizhat.com.      14400   IN      A       69.59.28.85
free.bizhat.com.        14400   IN      A       208.53.161.106
freeforums.bizhat.com.  14400   IN      A       208.53.161.107
freeinfo.bizhat.com.    14400   IN      A       67.228.37.136
freelance.bizhat.com.   14400   IN      A       67.228.37.136
friends.bizhat.com.     14400   IN      A       65.98.61.140
ftp.bizhat.com.         14400   IN      CNAME   bizhat.com.
gallery.bizhat.com.     14400   IN      A       69.59.28.85
games.bizhat.com.       14400   IN      A       67.228.37.136
gifts.bizhat.com.       14400   IN      CNAME   cms.bizhat.com.
git.bizhat.com.         14400   IN      A       67.228.104.123
gptcktm.bizhat.com.     14400   IN      CNAME   cms.bizhat.com.
guestbook.bizhat.com.   14400   IN      A       67.228.37.136
gujarat.bizhat.com.     14400   IN      CNAME   cms.bizhat.com.
hamradio.bizhat.com.    14400   IN      CNAME   cms.bizhat.com.
health.bizhat.com.      14400   IN      CNAME   cms.bizhat.com.
home.bizhat.com.        14400   IN      A       67.228.37.136
homebiz.bizhat.com.     14400   IN      A       67.228.37.136
hosted.bizhat.com.      14400   IN      A       67.228.37.136
hosting.bizhat.com.     14400   IN      A       67.228.37.136
hotels.bizhat.com.      14400   IN      CNAME   cms.bizhat.com.
htmltutorial.bizhat.com. 14400  IN      CNAME   cms.bizhat.com.
idukki.bizhat.com.      14400   IN      CNAME   cms.bizhat.com.
image.bizhat.com.       14400   IN      A       74.86.201.216
imagehost.bizhat.com.   14400   IN      A       67.228.104.120
images.bizhat.com.      14400   IN      A       74.86.201.216
img1.bizhat.com.        14400   IN      A       69.59.28.86
img2.bizhat.com.        14400   IN      A       76.76.18.24
img3.bizhat.com.        14400   IN      A       67.228.104.120
img4.bizhat.com.        14400   IN      A       208.53.161.108
img5.bizhat.com.        14400   IN      A       76.76.18.24
india.bizhat.com.       14400   IN      CNAME   cms.bizhat.com.
interactivecd.bizhat.com. 14400 IN      A       67.228.37.136
iptools.bizhat.com.     14400   IN      A       67.228.96.44
ishtam.bizhat.com.      14400   IN      A       67.228.37.136
jagathi.bizhat.com.     14400   IN      A       67.228.96.44
jayaram.bizhat.com.     14400   IN      CNAME   cms.bizhat.com.
jobs.bizhat.com.        14400   IN      A       76.76.18.23
jokes.bizhat.com.       14400   IN      A       67.228.37.136
kannur.bizhat.com.      14400   IN      CNAME   cms.bizhat.com.
karnataka.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
kasaragod.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
kashmir.bizhat.com.     14400   IN      CNAME   cms.bizhat.com.
kerala.bizhat.com.      14400   IN      CNAME   cms.bizhat.com.
kidsempire.bizhat.com.  14400   IN      CNAME   cms.bizhat.com.
kochi.bizhat.com.       14400   IN      CNAME   cms.bizhat.com.
koilparampil.bizhat.com. 14400  IN      CNAME   cms.bizhat.com.
kollam.bizhat.com.      14400   IN      CNAME   cms.bizhat.com.
kottayam.bizhat.com.    14400   IN      CNAME   cms.bizhat.com.
kovalam.bizhat.com.     14400   IN      CNAME   cms.bizhat.com.
kozhikode.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
kumarakom.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
kunchackoboban.bizhat.com. 14400 IN     A       67.228.96.44
labs.bizhat.com.        14400   IN      A       69.93.202.216
lifestyle.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
linuxcd.bizhat.com.     14400   IN      CNAME   cms.bizhat.com.
localhost.bizhat.com.   14400   IN      A       127.0.0.1
lonavala.bizhat.com.    14400   IN      CNAME   cms.bizhat.com.
lotus.bizhat.com.       14400   IN      CNAME   cms.bizhat.com.
mail.bizhat.com.        14400   IN      A       76.76.18.23
www.mail.bizhat.com.    14400   IN      A       76.76.18.23
malappuram.bizhat.com.  14400   IN      CNAME   cms.bizhat.com.
mammooty.bizhat.com.    14400   IN      CNAME   cms.bizhat.com.
mano.bizhat.com.        14400   IN      A       67.228.95.96
www.mano.bizhat.com.    14400   IN      A       67.228.95.96
mariasadanam.bizhat.com. 14400  IN      CNAME   cms.bizhat.com.
media.bizhat.com.       14400   IN      A       76.76.18.22
mohanlal.bizhat.com.    14400   IN      CNAME   cms.bizhat.com.
movies.bizhat.com.      14400   IN      A       74.86.201.216
munnar.bizhat.com.      14400   IN      CNAME   cms.bizhat.com.
music.bizhat.com.       14400   IN      A       67.228.37.136
news.bizhat.com.        14400   IN      A       67.228.96.44
newsletter.bizhat.com.  14400   IN      A       67.228.95.96
newstar.bizhat.com.     14400   IN      A       67.228.37.136
novel.bizhat.com.       14400   IN      A       67.228.37.136
palakkad.bizhat.com.    14400   IN      CNAME   cms.bizhat.com.
pallipuram.bizhat.com.  14400   IN      CNAME   cms.bizhat.com.
pallithode.bizhat.com.  14400   IN      CNAME   cms.bizhat.com.
pathanamthitta.bizhat.com. 14400 IN     CNAME   cms.bizhat.com.
pets.bizhat.com.        14400   IN      CNAME   cms.bizhat.com.
phpbb.bizhat.com.       14400   IN      CNAME   cms.bizhat.com.
phptutorial.bizhat.com. 14400   IN      CNAME   cms.bizhat.com.
postfix.bizhat.com.     14400   IN      CNAME   cms.bizhat.com.
print.bizhat.com.       14400   IN      CNAME   cms.bizhat.com.
qmail.bizhat.com.       14400   IN      CNAME   cms.bizhat.com.
radio.bizhat.com.       14400   IN      A       67.228.96.44
ranakpur.bizhat.com.    14400   IN      CNAME   cms.bizhat.com.
realestate.bizhat.com.  14400   IN      A       67.228.37.136
recipes.bizhat.com.     14400   IN      A       67.228.37.136
s1.bizhat.com.          14400   IN      A       76.76.18.23
*.s1.bizhat.com.        14400   IN      A       76.76.18.23
s2.bizhat.com.          14400   IN      A       76.76.18.21
*.s2.bizhat.com.        14400   IN      A       76.76.18.21
s3.bizhat.com.          14400   IN      A       76.76.18.21
*.s3.bizhat.com.        14400   IN      A       76.76.18.21
s4.bizhat.com.          14400   IN      A       76.76.18.21
*.s4.bizhat.com.        14400   IN      A       76.76.18.21
salu.bizhat.com.        14400   IN      CNAME   cms.bizhat.com.
sanjeevani.bizhat.com.  14400   IN      CNAME   cms.bizhat.com.
screensaver.bizhat.com. 14400   IN      A       67.228.37.136
scripts.bizhat.com.     14400   IN      A       67.228.37.136
search.bizhat.com.      14400   IN      A       67.228.37.136
sites.bizhat.com.       14400   IN      CNAME   cms.bizhat.com.
smartboss.bizhat.com.   14400   IN      A       174.37.154.236
sms.bizhat.com.         14400   IN      A       76.76.18.23
star.bizhat.com.        14400   IN      CNAME   cms.bizhat.com.
stefin.bizhat.com.      14400   IN      CNAME   cms.bizhat.com.
stmarys.bizhat.com.     14400   IN      CNAME   cms.bizhat.com.
www.stmarys.bizhat.com. 14400   IN      CNAME   cms.bizhat.com.
submit.bizhat.com.      14400   IN      A       67.228.37.136
sureshgopi.bizhat.com.  14400   IN      CNAME   cms.bizhat.com.
test.bizhat.com.        14400   IN      A       67.228.37.136
thanki.bizhat.com.      14400   IN      CNAME   cms.bizhat.com.
thiruvananthapuram.bizhat.com. 14400 IN CNAME   cms.bizhat.com.
thrissur.bizhat.com.    14400   IN      CNAME   cms.bizhat.com.
top100.bizhat.com.      14400   IN      A       76.76.18.23
tourism.bizhat.com.     14400   IN      CNAME   cms.bizhat.com.
tutorials.bizhat.com.   14400   IN      CNAME   cms.bizhat.com.
uploads.bizhat.com.     14400   IN      A       67.228.226.99
uploads.bizhat.com.     14400   IN      A       76.76.18.19
ftp.uploads.bizhat.com. 14400   IN      A       208.53.170.247
s1.uploads.bizhat.com.  14400   IN      A       127.0.0.1
s2.uploads.bizhat.com.  14400   IN      A       208.53.168.39
s3.uploads.bizhat.com.  14400   IN      A       208.53.168.13
s4.uploads.bizhat.com.  14400   IN      A       208.53.158.66
s5.uploads.bizhat.com.  14400   IN      A       67.159.61.214
s6.uploads.bizhat.com.  14400   IN      A       67.159.60.15
s7.uploads.bizhat.com.  14400   IN      A       66.90.104.210
s8.uploads.bizhat.com.  14400   IN      A       208.53.136.114
s9.uploads.bizhat.com.  14400   IN      A       66.90.104.184
www.uploads.bizhat.com. 14400   IN      A       67.228.226.99
uploads-nu-s54.bizhat.com. 14400 IN     A       76.76.18.23
varkala.bizhat.com.     14400   IN      CNAME   cms.bizhat.com.
video.bizhat.com.       14400   IN      A       67.228.116.84
s1.video.bizhat.com.    14400   IN      A       69.59.28.86
s2.video.bizhat.com.    14400   IN      CNAME   1wp-f2a00a0000000000.id.velocix.com.
static1.video.bizhat.com. 14400 IN      A       76.76.18.24
visitation.bizhat.com.  14400   IN      CNAME   cms.bizhat.com.
wayanad.bizhat.com.     14400   IN      CNAME   cms.bizhat.com.
webftp.bizhat.com.      14400   IN      A       208.53.161.106
webmaster.bizhat.com.   14400   IN      A       67.228.37.136
world.bizhat.com.       14400   IN      A       67.228.37.136
worldseven.bizhat.com.  14400   IN      A       127.0.0.2
www.bizhat.com.         14400   IN      CNAME   bizhat.com.
yearofdevil.bizhat.com. 14400   IN      A       67.228.37.136
yellowpages.bizhat.com. 14400   IN      A       67.228.95.96
yourname.bizhat.com.    14400   IN      CNAME   cms.bizhat.com.
youtubescript.bizhat.com. 14400 IN      A       67.228.192.156
bizhat.com.             86400   IN      SOA     dns10.hosthat.com. hostonnet.gmail.com. 2008091126 7100 7200 2419100 86400
;; Query time: 113 msec
;; SERVER: 67.228.226.101#53(67.228.226.101)
;; WHEN: Mon Jul  6 04:22:03 2009
;; XFR size: 199 records (messages 1, bytes 4605)

[root@vps3 poweradmin]#

See dig

November 23, 2020

mycomputer

These are some software/settings i have on my computer running Ubuntu 20.04

Steam store games on different Disk
GNOME Shell Extension
Install TeamSpeak Client on Ubuntu
Separate Google Hangout icon in Ubuntu 18.04/20.04

November 23, 2020
Steam store games on different Disk
I have a 250 GB SSD as boot drive. My steam games installed on a 2nd 2 TB hard disk. After reinstalling Ubuntu, i installed steam with.
```
apt install steam
```
Steam does not show the games installed on the 2 TB HDD.

To get the games work, i renamed steamapps folder, them created a symlink to directory on the 2 TB HDD where games are installed.

Stop steam, then do the following. /mnt/data/SteamLibrary/steamapps is the directory where my games are installed. Change it to whatever directory where your games are installed.
```
cd ~/.steam/debian-installation/
mv steamapps steamapps-old
ln -s /mnt/data/SteamLibrary/steamapps
```
Now start Steam, you will see the games.
November 23, 2020
GNOME Shell Extension
GNOME Shell Extensions allow you to add/modify features in Gnome Desktop. Gnome Desktop is used by Ubuntu.

Shell Extensions are stored in folder
```
/home/USER/.local/share/gnome-shell/extensions
```
On Ubuntu 20.04, i installed NoAnnoyance extension. This prevent Annoying Windows Ready notification.

https://extensions.gnome.org/extension/1236/noannoyance/

To install an extension, go to the web page of the extension, you will be asked to install a browser extension. Once browser etxtension installed, you need to install
```
sudo apt install chrome-gnome-shell
```
This is same for both Google Chrome and Firefox. Now you can go to any extension page, select “ON/OFF” button on the page to install an extension.

Extensions i use on Ubuntu 20.04

Ubuntu don’t have a quick way to switch between sound devices. For example switching between headphone and speaker. I used Sound Input & Output Device Chooser for very long. On 2021-03-30, it stopped working. I started using a differnt extension Audio output selector, this have less features, but do the work properly.

List all Gnome Extensions

To list all gnome extensions, run “gnome-extensions list”.
```
boby@sok-01:~$ gnome-extensions list
desktop-icons@csoriano
ubuntu-appindicators@ubuntu.com
ubuntu-dock@ubuntu.com
sound-output-device-chooser@kgshank.net
noannoyance@sindex.com
boby@sok-01:~$ 
```
To enable/disable an extension, use
```
gnome-extensions enable EXTENSION_NAME
gnome-extensions disable EXTENSION_NAME
```
Example
```
gnome-extensions disable sound-output-device-chooser@kgshank.net
```
November 23, 2020
Install TeamSpeak Client on Ubuntu
To install TeamSpeak client on Ubuntu, download latest version from

https://www.teamspeak.com/en/downloads/

Download page list both 32 and 64 bit versions. Most computers these days use 64 bit OS. So download 64 bit version unless you are using older computer with 32 bit OS.

On Ubuntu, you can find if you are using 32 or 64 bit version with command arch
```
boby@sok-01:~$ arch
x86_64
boby@sok-01:~$ 
```
Download latest version of TeamSpeak, as for this writing, latest verison is
```
wget https://files.teamspeak-services.com/releases/client/3.5.5/TeamSpeak3-Client-linux_amd64-3.5.5.run
```
Make it executable
```
chmod 755 TeamSpeak3-Client-linux_amd64-3.5.5.run
```
To extract it, run
```
./TeamSpeak3-Client-linux_amd64-3.5.5.run
```
This will cretae a folder with TeamSpeak files. Move it to /opt directory or any other folder you prefer.
```
mv TeamSpeak3-Client-linux_amd64 /opt/
```
Now you can start TeamSpeak from command line with command
```
/opt/TeamSpeak3-Client-linux_amd64/ts3client_runscript.sh
```
To create a shortcut file, create a desktop file
```
vi ~/.local/share/applications/teamspeak.desktop
```
Add following content
```
[Desktop Entry]
Name=TeamSpeak 3
Comment=TeamSpeak 3 VoIP Communicator
Exec=/opt/TeamSpeak3-Client-linux_amd64/ts3client_runscript.sh
Terminal=false
Type=Application
Categories=Network;Application;
Icon=/opt/TeamSpeak3-Client-linux_amd64/styles/default/logo-128x128.png
```
Now you will be able to find TeamSpeak 3 in Ubuntu Start menu/Dash.

See Ubuntu
November 22, 2020
configure: error: “curses not found”
When installing a software from source, i get errro
```
configure: error: "curses not found"
```
To fix this, install libncurses-dev
```
apt install libncurses-dev
```
See Errors
November 16, 2020
configure: error: “libevent not found”
When installing a software from source i get error
```
configure: error: "libevent not found"
```
To fix, install libevent-dev
```
apt install libevent-dev
```
See Errors
November 16, 2020

Category: Linux

Check For Bad Scripts

Extensions i use on Ubuntu 20.04

List all Gnome Extensions