==== Oracle Linux Tips ====

----

=== Serial Console ===
  * NON-EFI
<code>
# cat /etc/default/grub
GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)"
GRUB_DEFAULT=saved
GRUB_DISABLE_SUBMENU=true
GRUB_TERMINAL="console serial"
GRUB_SERIAL_COMMAND="serial --speed=115200 --unit=0 --word=8 --parity=no --stop=1"
GRUB_CMDLINE_LINUX="crashkernel=auto rd.lvm.lv=ol/root"
GRUB_CMDLINE_LINUX_DEFAULT="console=ttyS0,115200"
GRUB_DISABLE_RECOVERY="true"

# grub2-mkconfig -o /boot/grub2/grub.cfg
</code> 
\\ 

  * EFI
<code>
# cat /etc/default/grub
GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)"
GRUB_DEFAULT=saved
GRUB_DISABLE_SUBMENU=true
GRUB_TERMINAL="console serial"
GRUB_SERIAL_COMMAND="serial --speed=115200 --unit=0 --word=8 --parity=no --stop=1"
GRUB_CMDLINE_LINUX="crashkernel=auto rd.lvm.lv=ol/root rd.lvm.lv=ol/swap"
GRUB_CMDLINE_LINUX_DEFAULT="console=ttyS0,115200"
GRUB_DISABLE_RECOVERY="true"

# for f in /boot/vm*; do grubby --info $f; done
# for f in /boot/vm*; do grubby --remove-args="rhgb quiet" --args="console=ttyS0,115200" --update-kernel=$f; done
# for f in /boot/vm*; do grubby --info $f; done
# grub2-mkconfig -o /boot/efi/EFI/*/grub.cfg
</code>

----

=== iSCSI Initiator ====
  - Install the package <code># dnf install iscsi-initiator-utils</code>
  - Discover targets <code># iscsiadm -m discovery -t sendtargets -p SCSI_TARGET_SERVER</code>
  - Display target information <code># iscsiadm -m discoverydb -t st -p SCSI_TARGET_SERVER</code>
  - Establish a session <code># iscsiadm -m node -T iqn.XXX... -p SCSI_TARGET_SERVER:3260 -l</code>
  - Verify session <code># iscsiadm -m session -P 3</code>
  - When adding an iSCSI LUN to the fstab, use the _netdev option<code>UUID=xxx... /MP ext4 _netdev 0 0</code>
  - Log out of session<code># iscsiadm -m node -T iqn.XXX... -p SCSI_TARGET_SERVER:3260 --logout</code>
  - Remove target from database<code># iscsiadm -m node -T iqn.XXX... -p SCSI_TARGET_SERVER:3260 -o delete</code>
  - If target server has gone away, entries can be removed manually<code># rm -rf /var/lib/iscsi/nodes/TARGET</code>