The steps can be done when the disk is online; only creating the partition required a reboot for me.

Growing the filesystem

1. Create a physical LVM volume: pvcreate /dev/sdaN; check using pvdisplay

   $ pvcreate /dev/sdaN
     Physical volume "/dev/sdaN" successfully created
   

   $ pvdisplay
      --- Physical volume ---
     PV Name               /dev/sda1
     VG Name               vg-name
     ...
    
     --- Physical volume ---
     PV Name               /dev/sda2
     VG Name               vg-name
     ...
    
     "/dev/sdaN" is a new physical volume of "100.00 GiB"
     --- NEW Physical volume ---
     PV Name               /dev/sdaN
     VG Name
     PV Size               100.00 GiB
     Allocatable           NO
     PE Size               0
     Total PE              0
     Free PE               0
     Allocated PE          0
     ...
   

2. Extend the volume group: vgextend vg-name /dev/sdaN; check using lvdisplay

   $ vgextend vg-name /dev/sdaN
     Volume group "vg-name" successfully extended
   

   $ lvdisplay
    
     --- Logical volume ---
     LV Name                /dev/vg-name/root
     VG Name                vg-name
     ...
   

3. Extend the logical volume to all free space available: lvextend -l+100%FREE /dev/vg-name/root

   $ lvextend -l+100%FREE /dev/vg-name/root
   

4. Resize the file system: resize2fs /dev/mapper/vg--name-root

   $ resize2fs /dev/mapper/vg--name-root
   

Partition type code for LVM is 8e.

Some more useful commands

lvmdiskscan -l to scan for LVM physical volumes
vgdisplay -v to summarize lot of information about a volume group
lvs to find the logical volumes and there size; also try the --segments argument

posted at: 11:16 | path: /configuration | permanent link

Note to myself about let's encrypt auto-renew: Put letsencrypt in /etc/cron.weekly, edit the services that need to be restarted. The first snippet is for a relatively modern, systemd-enabled, system (Ubuntu 16.04), the second snippet target an ancient system (Ubuntu 14.04): The script assumes that the letsencrypt tool in installed (via Ubuntu PPA).

Recent systems:

#!/bin/sh
letsencrypt renew --pre-hook "systemctl stop apache2" --post-hook "systemctl start apache2"
res=$(find /etc/letsencrypt/live/ -type l -mtime -1)
if [ -n "$res" ]; then
  echo "letsencrypt: new keys"
  systemctl restart apache2
  systemctl restart postfix
  systemctl restart dovecot
else
  echo "letsencrypt: nothing to do"
fi

Ancient systems:

#!/bin/sh
letsencrypt renew --pre-hook "/etc/init.d/apache2 stop" --post-hook "/etc/init.d/apache2 start"
res=$(find /etc/letsencrypt/live/ -type l -mtime -1)
if [ -n "$res" ]; then
  echo "letsencrypt: new keys"
  /etc/init.d/apache2 restart
  #/etc/init.d/postfix restart
  #/etc/init.d/dovecot restart
else
  echo "letsencrypt: nothing to do"
fi

posted at: 10:37 | path: /configuration | permanent link

Here are my citations per year (from 2003 to 2018) according to Google scholar:

Google Scholar thinks I have reached h-18.

posted at: 15:32 | path: /academic | permanent link