Finding Public IP Addresses (GW) from terminal
SSH authetication in dockerfile automatic
Get container id within that container
unknown terminal in dockerfile solution
nfs-mounting inside a container
sudo permission unauthenticated
ssh passwordless authetication
ssh passwordless and userless authetication
Windows Server 2012 R2 -- Free product key
Find files installed by a package
Clear RAM Memory Cache, Buffer and Swap Space on Linux
Docker sort memory usage by container
Once you have installed the evaluation copy you may see that it is not activated and when you try and activate, it will ask for a product key.
If you get this instead of it automatically activating for you, then all you need to do is to run the following command from an elevated command prompt:
slmgr.vbs -rearm
This should then automatically rearm your trial for 180 days. I have tested this several times, apparently you can rearm your trial version up to five times which will give you around 2 and a half years of Windows Server 2012 R2 . link
http://patorjk.com/software/taag
https://www.sejda.com/pdf-editor
export LANGUAGE="en_US.UTF-8"
echo 'LANGUAGE="en_US.UTF-8"' >> /etc/default/locale
echo 'LC_ALL="en_US.UTF-8"' >> /etc/default/locale # exit and login again
dpkg-reconfigure locales
or
echo """
LANGUAGE=\"en_US.UTF-8\"
LANG=\"en_US.UTF-8\"
LC_ALL=\"en_US.UTF-8\"
JAVA_HOME=\"/usr/lib/jvm/java-8-openjdk-amd64\"
""" >> /etc/environment
curl -s https://raw.githubusercontent.com/sivel/speedtest-cli/master/speedtest.py | python -
Finding Public IP Addresses (GW) from terminal
dig +short myip.opendns.com @resolver1.opendns.com
curl ifconfig.me
curl icanhazip.com
curl ipecho.net/plain
curl ifconfig.co
https://www.cyberciti.biz/faq/how-to-find-my-public-ip-address-from-command-line-on-a-linux/
Class Private Networks Subnet Mask Address Range
A 10.0.0.0 255.0.0.0 10.0.0.0 - 10.255.255.255
B 172.16.0.0 - 172.31.0.0 255.240.0.0 172.16.0.0 - 172.31.255.255
C 192.168.0.0 255.255.0.0 192.168.0.0 - 192.168.255.255
SSH authetication in dockerfile automatic
echo "Host github.com\n\tStrictHostKeyChecking no\n" > /root/.ssh/config
Get container id within that container
cat /proc/self/cgroup | grep "cpu:/" | sed 's/\([0-9]\):cpu:\/docker\///g'
error : unknown terminal in dockerfile solution
export TERM=xterm
nfs-mounting inside a container
give privileges for docker container "--privileged" while running the containier
(java 1.8)
apt-get update \
&& echo oracle-java8-installer shared/accepted-oracle-license-v1-1 select true | /usr/bin/debconf-set-selections \
&& apt-get install -y python-software-properties software-properties-common \
&& add-apt-repository -y ppa:webupd8team/java \
&& apt-get -y update \
&& apt-get install -y nano wget unzip locate oracle-java8-installer \
&& update-java-alternatives --set java-8-oracle \
&& apt-get install oracle-java8-set-default && java -version
apt-get install openjdk-8-jdk -y
apt-get update
apt-get install java-common
dpkg --install java-1.8.0-amazon-corretto-jdk_8.212.04-2_amd64.deb
https://docs.aws.amazon.com/corretto/latest/corretto-8-ug/generic-linux-install.html
for go to a particular line in nano edit
nano +107 filename
inside >>
(ctrl) + (shift) + (-)
giving user to run sudo without password
1) add a user
2) add user in sudo group
3) edit sudoer file # nano /etc/sudoers or visudo
4) add this line
username ALL=(ALL) NOPASSWD: ALL
Setup SSH for Auto Login without a Password
On server
ssh-keygen # this command will create a .ssh directory under home if it doent exist
ssh-copy-id servername # this will copy the public key to server with name of authorized_keys
chmod 600 authorized_keys
or
ssh-keygen -t rsa # (hit return through prompts)
mv id_rsa.pub >> authorized_keys
chmod 600 authorized_keys
scp authorized_keys user@client ip:/home/ubuntu/.ssh/
check on client side and try to login from server
http://www.rebol.com/docs/ssh-auto-login.html
Setup SSH for Auto Login without a Password and without user
cd .ssh
ssh-keygen -t rsa (hit return through prompts)
mv id_rsa.pub >> authorized_keys
chmod 600 authorized_keys
scp authorized_keys user@client ip:/home/ubuntu/.ssh/
nano .ssh/config
the public key must be provided in that user's .ssh/authorized_keys
Example 1 >>
Host digital
Hostname 192.168.1.234
User ubuntu
IdentityFile /home/ubuntu/Desktop/digital
ssh digital # in here, login as ubuntu and private key taken from IdentityFile path
Example 2 >>
Host akhil
Hostname 192.168.1.235
User root
IdentityFile /home/ubuntu/Desktop/digital
ssh akhil # in here, login as root and private key taken from IdentityFile path
scp with particular port
scp -r -P 2233 -i /path/to/name.pem user@ip-address:/path/to/src /path/to/dest
tomcat download site
http://www-us.apache.org/dist/tomcat/
env MYSQL_ROOT ubuntu >> will work “_”
env MYSQL-ROOT ubuntu >> will not work “-”
https://www.linkedin.com/pulse/solution-javanetsocketexception-too-many-open-files-divyang-shah https://www.cyberciti.biz/faq/linux-increase-the-maximum-number-of-open-files/
The user limit on the total number of inotify watches
sysctl fs.inotify
echo 999999 | sudo tee -a /proc/sys/fs/inotify/max_user_watches && echo 999999 | sudo tee -a /proc/sys/fs/inotify/max_queued_events && echo 999999 | sudo tee -a /proc/sys/fs/inotify/max_user_instances && sudo sysctl -p
https://github.com/facebook/watchman/issues/163
deleting tags form repos in a sec
git tag -l
git tag -d $(git tag -l)
git fetch
git push origin --delete $(git tag -l) # Pushing once should be faster than multiple times.
git tag -d $(git tag -l)
git tag -l
RPM based distro
rpm --query --list <package-name>
eg: rpm --query --list libcgroup | less
Clear PageCache only.
sync; echo 1 > /proc/sys/vm/drop_caches
Clear dentries and inodes.
sync; echo 2 > /proc/sys/vm/drop_caches
Clear PageCache, dentries and inodes.
sync; echo 3 > /proc/sys/vm/drop_caches
docker stats --no-stream --format "table {{.Name}}\t{{.Container}}\t{{.CPUPerc}}\t{{.MemUsage}}" | sort -k 4 -h