RHEL 7 GRUB reinstall

 grub2-install /dev/sda

grub2-mkconfig -o /boot/grub2/grub.cfg

RHEL boot with network - Troubleshoot 'Login error on ssh and console'

Boot to Troubleshooting mode and select 1st option:

chroot /mnt/sysimage 

Run below command.

Login error: tail - f /var/log/secure - Found pam module missing. /usr/lib64/security.

reinstalled pam after connecting to network. But found pam_unix.so gettting deleted. Disabled mcafee and found it's working. 

ip link

 ip link set dev eth0 up

ip addr add 192.168.122.250/24 dev eth0

ip route add default via 192.168.122.1

https://access.redhat.com/solutions/2626631

OS update ansible playbook

 [cinil@patchmanager ansible_playbooks]$ cat osupdate-preparation.yml

---

  - name: Osupdate

    hosts: all

    become: yes

    become_user: root

    tasks:

      - name: taking backup of important files.

        shell: mkdir /var/tmp/security_patching_bkp;cd /var/tmp/security_patching_bkp;df -h>df.txt;ifconfig -a>ifconfig.txt;uname -a>uname.txt;ps -eaf>ps.txt

        register: result

      - name: Clean yum

        shell: yum clean all

        register: yumclean

      - name: yum list security

        shell: yum list-security > /var/tmp/security_patching_bkp/yum_list-security.txt

        register: yumlist_security

      - name: Yum security update

        shell: yum update --security -y

        register: yumsecurityupdate

      - name: Yum security update skip-broken

        shell: yum update --security -y --skip-broken

        register: yumsecurityupdateskipb

      - name: Count the boot files before reboot

        shell: cd /boot/;ls |grep `rpm -q --last kernel | awk 'NR==1{sub(/kernel-/,"");print $1}'`|wc -l

        register: countbootfiles

      - fail:

          msg: "Kernel update failed"

        when: countbootfiles.stdout != "5"

[cinil@patchmanager ansible_playbooks]$

[cinil@patchmanager ansible_playbooks]$ cat Osupdate-Reboot.yml

---

  - name: Os-Security update Server reboot

    hosts: all

    become: yes

    become_user: root

    tasks:

      - name: Count the boot files before reboot

        shell: cd /boot/;ls |grep `rpm -q --last kernel | awk 'NR==1{sub(/kernel-/,"");print $1}'`|wc -l

        register: countbootfiles

      - name: Checking reboot required or not

        shell: LAST_KERNEL=$(rpm -q --last kernel | awk 'NR==1{sub(/kernel-/,""); print $1}'); CURRENT_KERNEL=$(uname -r); if [ $LAST_KERNEL != $CURRENT_KERNEL ]; then echo 'reboot'; else echo 'no'; fi

        ignore_errors: true

        register: reboot_hint

      - name: Rebooting if required...

        shell: ahutdown -r now "Reboot required for updated kernel"

        async: 0

        poll: 0

        when: reboot_hint.stdout.find("reboot") != -1 and countbootfiles.stdout.find("5") != -1

        register: rebooting

      - name: Waiting for thing to reboot

        pause: seconds=180

        when: rebooting|changed

      - fail:

         msg: "Server not rebooted due to Kernel update fail or wrong reboot"

        when: reboot_hint.stdout.find("reboot") == -1 or countbootfiles.stdout.find("5") == -1

[cinil@patchmanager ansible_playbooks]$

Move root disk in LVM

 https://access.redhat.com/solutions/1609793

fdisk /dev/sdc        ---- Create partition similar to root disk also mark boot disk label.

mkfs.xfs /dev/sdc1   --- make boot disk.

mount /dev/sdc1 /mnt

cp -a /boot/* /mnt/

grub2-install --boot-directory=/mnt /dev/sdc

Update /etc/fstab

blkid /dev/sdc1

Reboot the system.

grub2-mkconfig -o /boot/grub2/grub.cfg

Extend VG

vgextend systemvg /dev/sdc2

move LV one by one

pvmove -b -n rootlv /dev/sda2 /dev/sdc2

Monitor the progress

lvs -a -o+devices

extend linux file system

 pvcreate /dev/sda5

pvs
vgs
vgextend vg_algosec /dev/sda5
vgs
lvextend -L +100G /dev/mapper/vg_algosec-vg_system
lvs
resize2fs /dev/mapper/vg_algosec-vg_system

 

lvextend -L +300G /dev/mapper/vg_algosec-vg_data
lvs
resize2fs /dev/mapper/vg_algosec-vg_data