diff -Nru monitoring-plugins-2.2/debian/changelog monitoring-plugins-2.2/debian/changelog
--- monitoring-plugins-2.2/debian/changelog	2020-05-02 14:35:43.000000000 +0800
+++ monitoring-plugins-2.2/debian/changelog	2022-06-27 18:12:04.000000000 +0800
@@ -1,3 +1,12 @@
+monitoring-plugins (2.2-3ubuntu4) bionic; urgency=medium
+
+  * d/p/exclude-tmpfs-squashfs-tracefs.patch: Ignore artificial filesystems
+    that trigger false-positive DISK CRITICAL checks due to reporting as at
+    100% capacity.
+    (LP: #1827159)
+
+ -- Zhang Hua <joshua.zhang@canonical.com>  Mon, 27 Jun 2022 18:12:04 +0800
+
 monitoring-plugins (2.2-3ubuntu3) bionic; urgency=medium
 
   [Haw Loeung]
diff -Nru monitoring-plugins-2.2/debian/patches/exclude-tmpfs-squashfs-tracefs.patch monitoring-plugins-2.2/debian/patches/exclude-tmpfs-squashfs-tracefs.patch
--- monitoring-plugins-2.2/debian/patches/exclude-tmpfs-squashfs-tracefs.patch	1970-01-01 08:00:00.000000000 +0800
+++ monitoring-plugins-2.2/debian/patches/exclude-tmpfs-squashfs-tracefs.patch	2022-06-27 18:11:40.000000000 +0800
@@ -0,0 +1,57 @@
+Description: Exclude tmpfs, squashfs, and tracefs.
+ These synthetic filesystems always report 100% disk usage by design, so
+ can generate false-positive "disk full" alerts.  While it is possible to
+ exclude these via command line arguments, it is more convenient to
+ ignore them directly by the tool taking into account if they have been
+ included by options or not and if a mount point has been provided in
+ the args.
+Author: Bryce Harrington <bryce@canonical.com>
+        Miriam España Acebal <miriam.espana@canonical.com>
+Bug-Ubuntu: https://bugs.launchpad.net/nagios-charm/+bug/1827159
+            https://bugs.launchpad.net/ubuntu/+source/monitoring-plugins/+bug/1940916
+Forwarded: yes, https://github.com/monitoring-plugins/monitoring-plugins/pull/1749
+Last-Update: 2019-11-07
+---
+ plugins/check_disk.c | 3 +++
+ 1 file changed, 3 insertions(+)
+
+Index: monitoring-plugins-2.2/plugins/check_disk.c
+===================================================================
+--- monitoring-plugins-2.2.orig/plugins/check_disk.c
++++ monitoring-plugins-2.2/plugins/check_disk.c
+@@ -417,7 +417,7 @@ double calculate_percent(uintmax_t value
+ int
+ process_arguments (int argc, char **argv)
+ {
+-  int c, err;
++  int c, err, i;
+   struct parameter_list *se;
+   struct parameter_list *temp_list = NULL, *previous = NULL;
+   struct mount_entry *me;
+@@ -467,11 +467,11 @@ process_arguments (int argc, char **argv
+     {0, 0, 0, 0}
+   };
+ 
++  char filesystems[3][10] = { "tmpfs", "squashfs", "tracefs" };
++
+   if (argc < 2)
+     return ERROR;
+ 
+-  np_add_name(&fs_exclude_list, "iso9660");
+-
+   for (c = 1; c < argc; c++)
+     if (strcmp ("-to", argv[c]) == 0)
+       strcpy (argv[c], "-t");
+@@ -785,6 +785,12 @@ process_arguments (int argc, char **argv
+     mult = (uintmax_t)1024 * 1024;
+   }
+ 
++  for (i = 0; i < 3; i++)
++    if (!np_find_name (fs_include_list, filesystems[i]) && (path_selected == FALSE))
++      np_add_name(&fs_exclude_list, filesystems[i]);
++
++  np_add_name(&fs_exclude_list, "iso9660");
++
+   return TRUE;
+ }
+ 
diff -Nru monitoring-plugins-2.2/debian/patches/series monitoring-plugins-2.2/debian/patches/series
--- monitoring-plugins-2.2/debian/patches/series	2020-05-02 14:35:43.000000000 +0800
+++ monitoring-plugins-2.2/debian/patches/series	2022-06-27 18:11:27.000000000 +0800
@@ -5,3 +5,6 @@
 12_check_apt_only_crit
 13_check_apt_list_packages
 14_check_http_socket_timeouts
+
+# Ubuntu
+exclude-tmpfs-squashfs-tracefs.patch