rpm useful commands

list files installed by an INSTALLED rpm (for an UNINSTALLED rpm, add -p and provide full path to .rpm file):

rpm -ql nginx.x86_64

or also (if the rpm is not installed yet) repoquery --list nginx.x86_64

verify that rpm installed files have not been tampered

rpm -V nginx.x86_64

display the postinstall and postuninstall scripts

rpm -q --scripts nginx.x86_64

which rpm provides a given file:

rpm -q --whatprovides /usr/sbin/nginx
or also
rpm -qf /usr/sbin/nginx

for a REALLY verbose verification output:

rpm -Vvv nginx.x86_64



Ref:

http://ftp.rpm.org/max-rpm/s1-rpm-verify-what-to-verify.html


https://www.cyberciti.biz/howto/question/linux/linux-rpm-cheat-sheet.php fantastic all-in-one rpm cheat sheet

Linux misc (iptables, dig, rpm)

echo $LANG
en_US.UTF-8

CTRL-SHIFT-U allows you to enter the 4 letters for a Unicode character (eg 03bb is greek lambda)

localectl

System Locale: LANG=en_US.UTF-8
VC Keymap: it
X11 Layout: it,us
X11 Variant: ,

to change locale:
localectl set-locale LANG=fr_FR.utf8

cat /etc/locale.conf
LANG="en_US.UTF-8"

list all available language packs:
yum langavailable

list installed language packs:
yum langlist


iptables tutorial instructions: https://www.howtogeek.com/177621/the-beginners-guide-to-iptables-the-linux-firewall/

sudo iptables -L -v
sudo iptables -F
sudo cat /etc/sysconfig/iptables


network:
dig
systemctl status firewalld
systemctl status NetworkManager


history: remove line numbers by adding to .bash_profile
HISTTIMEFORMAT="$(echo -e '\r\e[K')"

#rpm list all packages
rpm -qa | grep ansible
#this installs 1.1 without removing 1.0 if exists
rpm -ivh some-package-1.1
#this updates (if existing) 1.0 to 1.1
rpm -Uvh some-package-1.1

rpm tutorial

https://rpm-packaging-guide.github.io/#preparing-software-for-packaging

https://rpm-guide.readthedocs.io/en/latest/rpm-guide.html


sudo yum install gcc rpm-build rpm-devel rpmlint make python bash coreutils diffutils patch rpmdevtools

cd /home/centos
mkdir rpmtest
cd rpmtest/
vi hello-world.spec

Name:       hello-world
Version:    1
Release:    1
Summary:    Most simple RPM package
License:    FIXME

%description
This is my first RPM package, which does nothing.

%prep
# we have no source, so nothing here

%build
cat > hello-world.sh <<EOF
#!/usr/bin/bash
echo Hello world
EOF

%install
mkdir -p %{buildroot}/usr/bin/
install -m 755 hello-world.sh %{buildroot}/usr/bin/hello-world.sh

%files
/usr/bin/hello-world.sh

%changelog
# let's skip this for now

rpmdev-setuptree
rpmbuild -ba hello-world.spec
cd /home/centos/rpmbuild/
find .
#install
sudo rpm -i -f ./RPMS/x86_64/hello-world-1-1.x86_64.rpm
hello-world.sh
which hello-world.sh
cat /usr/bin/hello-world.sh
#find package
rpm -qa | grep hello
#delete
sudo rpm -e hello-world-1-1.x86_64
#
cd /home/centos/rpmbuild/
sudo rpm -qpi ./RPMS/x86_64/hello-world-1-1.x86_64.rpm

Name        : hello-world
Version     : 1
Release     : 1
Architecture: x86_64
Install Date: (not installed)
Group       : Unspecified
Size        : 33
License     : FIXME
Signature   : (none)
Source RPM  : hello-world-1-1.src.rpm
Build Date  : Mon 03 Jun 2019 09:19:39 PM CEST
Build Host  : localhost
Relocations : (not relocatable)
Summary     : Most simple RPM package
Description :
This is my first RPM package, which does nothing.

This is to list the content of a rpm file without installing it:
rpm -q -filesbypkg -p filename.rpm
or also simply:
sudo rpm -ql hello-world-1-1.x86_64


To extract:

rpm2cpio ./RPMS/x86_64/hello-world-1-1.x86_64.rpm > /tmp/hello.cpio

and then

cpio -i --make-directories < /tmp/hello.cpio this will create under the current folder the file usr/bin/hello-world.sh See this nice presentation