Update the kernel package, add gpg key to repo

Question 1

Update kernel package

Answer 1

Normally you may do yum upgrade
In case to do this manually:
1. yum clean all
2. yum list kernel => yum will download fresh updates from repos
3. uname -r => to compare output of current version with yum list kernel
4. yumdownloader kernel
5. rpm -ivh kernel-1…. => dependencies error
6. yum install packages listed in dependencies error
7. reboot

__________
Look into ls /boot for new kernel and initramfs
if initramfs file with new kernel is not found, run
dracut to create this.

Question 2

Modify system bootloader

Answer 2

1. grub2-set-default n
n- number of kernel
grub2-set-default 0 -the most recent version
grub2-set-default 1
2. reboot

Question 3

Add gpgkey to repo

Answer 3

1. yum-config-manager –add-repo=https://dl.fedoraproject.org/pub/epel/8/Everything/x86_64/
   new repo in /etc/yum.repos.d/dl.fedoraproject.org_pub_epel_8_Everything_x8664.repo
2. Go to https://dl.fedoraproject.org/pub/epel/ where there is respective gpg key
   wget https://dl.fedoraproject.org/pub/epel/RPM-GPG-KEY-EPEL-8
   or
   wget -O /etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-8 https://dl.fedoraproject.org/pub/epel/RPM-GPG-KEY-EPEL-8
3. cp /home/user/RPM-GPG-KEY-EPEL-8 /etc/pki/pm-gpg/
4. vim /etc/yum.repos.d/dl.fedoraproject.org_pub_epel_8_Everything_x8664.repo
   gpgcheck=1
   gpgkey=file:///etc/pki/pm-gpg/RPM-GPG-KEY-EPEL-8
   :wq