This system is running Ubuntu Jaunty Jackalope AMD64, on a manual installation from the alternate CD.

How do I check whether:

1) I have an activated swap partition
2) It is functioning with encryption

Thank you!



My output is:

Quote:
Filename Type Size Used Priority
/dev/mapper/cswap partition 3903784 0 -1

Quote:
free -m
total used free shared buffers cached
Mem: 1986 631 1354 0 28 198
-/+ buffers/cache: 403 1582
Swap: 3812 0 3812

Quote:
blkid
/dev/sda1: UUID="9143ef04-c761-4b31-a7d2-684bec057db6" TYPE="ext4"
/dev/sda5: UUID="cec2575c-8f68-4bda-ac41-9e18de4a936c" TYPE="crypt_LUKS"
/dev/sda6: UUID="8f048d4c-d97e-4aa4-a532-9785d28f57e4" TYPE="crypt_LUKS"
/dev/sda7: UUID="0199c0a3-01de-4764-a419-79131caa85ae" TYPE="crypt_LUKS"
/dev/sdb5: UUID="e5a359ee-f43f-4294-a089-14557f2408b2" TYPE="crypt_LUKS"
/dev/mapper/sda5_crypt: UUID="294eaed0-62ea-4e45-9f87-c80cd287a811" TYPE="ext4"
/dev/mapper/sda6_crypt: UUID="03baf5cd-3206-4f6a-9dd8-56650159c5c1" TYPE="ext4"
/dev/mapper/sda7_crypt: UUID="be9724c3-bc67-409d-902d-b9139e5a6083" TYPE="ext4"
/dev/mapper/sdb5_crypt: UUID="84ba0426-641e-4b1e-a39d-938d3490014f" TYPE="ext4"
From my fstab:

Quote:
# /etc/fstab: static file system information.
#
# Use 'vol_id --uuid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc defaults 0 0
/dev/mapper/sda5_crypt / ext4 relatime,errors=remount-ro 0 1
/dev/mapper/sda7_crypt /backup ext4 relatime 0 2
# /boot was on /dev/sda1 during installation
UUID=9143ef04-c761-4b31-a7d2-684bec057db6 /boot ext4 relatime 0 2
/dev/mapper/sdb5_crypt /home ext4 relatime 0 2
/dev/mapper/sda6_crypt /opt ext4 relatime 0 2
/dev/scd0 /media/cdrom0 udf,iso9660 user,noauto,exec,utf8 0 0
/dev/fd0 /media/floppy0 auto rw,user,noauto,exec,utf8 0 0
/dev/mapper/cswap none swap sw 0 0

Quote:
cat /etc/initramfs-tools/conf.d/resume
cat: /etc/initramfs-tools/conf.d/resume: No such file or directory

Use sudo and run the command 'fdisk -l'.

On my system it looks like this...

As far as I know, swap is not encrypted. It uses another file system, unique to a swap partition.

Free command can show some swap information as see in prior post.

Also if your fstab a device with "swap" it indicates it is starting a swap device at start up.

You can see details of swap by typing "cat /proc/swap".

I've never heard of encrypted swap and would imagine it would slow things down quite a bit if it existed. Swap is an adjunct to memory. For most purposes swap is only used to preallocate "virtual" memory (the combination of real memory and swap) to processes as you start them.

These days you don't really "swap" out you "page" out and the pages are going to swap. This occurs as pages age/become less used and ideally won't really be needed again. It is faster to page back in from swap than to go get it from original location again but just barely - both require a disk read which is incredibly slow compared to memory. You want swap to allow for the preallocation and the page outs but you don't want to be doing excessive page ins.