Note: this is for Debian/Ubuntu Systems.
When applying kernel upgrades, typically a reboot is required. Typically a FSCK (disk check) is scheuled every 6 months (or number of mount times). A fsck can take quite a long time to scan the disks to see if there are any errors, especially with large disks. Wouldn't it be nice to know if a fsck will happen at the next reboot? And then you can plan for more downtime.
tune2fs -l /dev/sda1
It tells you when the next fsck will be run (Next check after:). See below for an example.
twister:~# tune2fs -l /dev/sda1 tune2fs 1.41.3 (12-Oct-2008) Filesystem volume name: <none> Last mounted on: <not available> Filesystem UUID: 451286b3-e9b0-43fe-8684-7fbc1dc611ed Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Filesystem features: has_journal filetype needs_recovery sparse_super Default mount options: (none) Filesystem state: clean Errors behavior: Continue Filesystem OS type: Linux Inode count: 393216 Block count: 786432 Reserved block count: 31457 Free blocks: 370519 Free inodes: 326179 First block: 0 Block size: 4096 Fragment size: 4096 Blocks per group: 32768 Fragments per group: 32768 Inodes per group: 16384 Inode blocks per group: 512 Filesystem created: Tue Sep 12 17:23:59 2006 Last mount time: Wed Apr 29 23:02:37 2009 Last write time: Wed Apr 29 23:02:37 2009 Mount count: 5 Maximum mount count: 32 Last checked: Fri Jan 30 08:28:42 2009 Check interval: 15552000 (6 months) Next check after: Wed Jul 29 09:28:42 2009 Reserved blocks uid: 0 (user root) Reserved blocks gid: 0 (group root) First inode: 11 Inode size: 128 Journal inode: 8 First orphan inode: 182499 Default directory hash: tea Directory Hash Seed: 1602904f-b5d3-4e6b-aac2-2e9b3a9964da Journal backup: inode blocks