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Remove Extended Attributes on Mac

If you have a file with @ sign at end, this is how to remove extended attributes on the Mac OS.

Example.

ls -l
-rwxr-xr-x@  4 username  staff   128 Mar 24 10:51 sample.txt

Remove extended attributes.

xattr -c sample.txt

Result

ls -l
-rwxr-xr-x  4 username  staff   128 Mar 24 10:51 sample.txt

AWS ELB SSL Listener

Here’s how to update SSL certificates to AWS ELB.

Import SSL certificate

aws acm import-certificate \
--certificate fileb://example.crt \
--private-key fileb://example.key \
--certificate-chain fileb://example-bundle.crt \
--tags Key=Name,Value=mydomain.com_20220107 \
--profile default

Add SSL to a listener.

aws elbv2 add-listener-certificates \
--listener-arn arn:aws:elasticloadbalancing:us-east-1:xxxxxxxxxxxxx:listener/app/elbname/xxxxxxxxxxxxxxxx/xxxxxxxxxxxxxxxx \
--certificates CertificateArn=arn:aws:acm:us-east-1:xxxxxxxxxxxx:certificate/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxxx \
--profile default

Modify listener. Set SSL certificate as default.

aws elbv2 modify-listener \
--listener-arn arn:aws:elasticloadbalancing:us-east-1:xxxxxxxxxxxxx:listener/app/elbname/xxxxxxxxxxxxxxxx/xxxxxxxxxxxxxxxx \
--certificates CertificateArn=arn:aws:acm:us-east-1:xxxxxxxxxxxx:certificate/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxxx \
--profile default

Remove SSL from a listener.

aws elbv2 remove-listener-certificates \
--listener-arn arn:aws:elasticloadbalancing:us-east-1:xxxxxxxxxxxxx:listener/app/elbname/xxxxxxxxxxxxxxxx/xxxxxxxxxxxxxxxx \
--certificates CertificateArn=arn:aws:acm:us-east-1:xxxxxxxxxxxx:certificate/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxxx \
--profile default

Rebuild Docker containers

How to rebuild your application from scratch using Docker.

#!/bin/bash
docker-compose down -v
docker rmi $(docker images -a -q)
docker-compose up -d
docker-compose restart -t 10

Steps

  • Purge the containers.
  • Delete docker images.
  • Reinitiate docker.
  • Restart docker.

Stop and remove all Docker containers

How to stop and remove all Docker containers.

Stop all containers

$ docker kill $(docker ps -q)

Remove all containers

$ docker rm $(docker ps -a -q)

Delete all docker images

$ docker rmi $(docker images -q)

Delete lines using sed

How to delete a line containing a pattern using sed.

Contents of test.txt.

$ cat test.txt
one
two
three

Delete a line matching the string “one.”

sed -i '/one/d' test.txt

Display test.txt

$ cat test.txt
two
three

Remove Oracle Java

Here’s a script that removes Oracle Java on your system. Installs OpenJDK Hotspot as a replacement.

#!/bin/bash
# set env
oracle_jre_version="jdk1.8.0_172"
open_jre_version="java-1.8.0-openjdk"
# REMOVE LINKS
deljdk () {
	sudo update-alternatives --remove "java" "/usr/lib/jvm/$oracle_jre_version/bin/java"
	sudo update-alternatives --remove "javac" "/usr/lib/jvm/$oracle_jre_version/bin/javac"
	sudo update-alternatives --remove "javaws" "/usr/lib/jvm/$oracle_jre_version/bin/javaws"
}
# REMOVE RPM
delrpm () {
	jdk=$(rpm -qa | grep jdk-1.7)
	rpm -e $jdk
	jdk=$(rpm -qa | grep jdk1.8)
	rpm -e $jdk
	sudo rm -rf /usr/java/jdk*
}
# REMOVE SYMBOLIC LINKS
delsym () {
	rm /usr/java/default /usr/java/latest
	rm /usr/lib/mozilla/plugins/libnpjp2.so
	rm /usr/lib/mozilla/plugins/libnpjp2.so
}
# INSTALL OPENJDK
addjdk () {
	cd /usr/java
	rm -f /usr/java/OpenJDK8U-jdk_x64_linux_hotspot_8u302b08.tar.gz
	wget --no-check-certificate https://10.49.39.125/download/OpenJDK8U-jdk_x64_linux_hotspot_8u302b08.tar.gz
	tar xzf OpenJDK8U-jdk_x64_linux_hotspot_8u302b08.tar.gz
	chown -R username:username /usr/java/jdk8u302-b08
}
# ADD PATH
addpath () {
	sed -i '/jdk8u302-b08/d' /home/username/.zshrc
	sed -i '/jdk8u302-b08/d' /home/username/.profile
	echo 'export PATH=/usr/java/jdk8u302-b08/bin:$PATH' | tee -a ~/.bashrc
	echo 'export PATH=/usr/java/jdk8u302-b08/bin:$PATH' | tee -a /home/username/.zshrc
	echo 'export PATH=/usr/java/jdk8u302-b08/bin:$PATH' | tee -a /home/username/.profile
	chown username:username /home/username/.zshrc
	chown username:username /home/username/.profile
}
deljdk
delrpm
delsym
addjdk
addpath

Bash Aliases

Create an alias.

alias gcloud='docker run --rm -ti --volumes-from gcloud-config google/cloud-sdk:latest gcloud'

Remove an alias.

unalias gcloud