mounting solaris

por | 6 agosto, 2008

Mounting the new filesystem

Following the letter of the law now you should fsck your new filesystem prior to mounting it – feel free. What you really want to do however is mount it so that you check it out. You can actually mount a filesystem on ANY directory, though it ought to be an empty one. There is an empty directory just for this purpose – /mnt;

    sun# mount /dev/dsk/c0t1d0s5 /mnt
    sun# df -k /mnt
    Filesystem            kbytes    used    avail capacity  Mounted on
    /dev/dsk/c0t1d0s5    2100583      10  2100573     0%    /mnt
    sun# ls -l /mnt
    total 62
    drwxrwxrwx   4 root     root         512 Jan  2  1999 lost+found 
    sun# umount /mnt

Here we are using /mnt as a mount point. More about these in The Filesystem explained – Mount Points

When you are content umount the filesystem with ‘umount /mnt’. Now you need to make things permanent – /etc/vfstab.

Swap Partitions – a.k.a. Swap Device

Solaris uses multiple swap partitions in parallel and shifting some of the paging load off the main system disk can make a big difference. By convention swap partitions should be placed on partition #1. This is however only a convention – nothing relies on it.

Notes: The slightest hiccup on a disk holding a swap partition can cause the system to crash. If you have any doubts about your new disk do not use it for this purpose.
It doesn’t make any sense to put multiple swap partitions on a single disk – this can actually degrade performance.

Once you have a partition free and available, you activate it by using the ‘swap -a’ command.

Be very careful here if you get this wrong and specify a partition that has a filesystem on it, well it won’t after this command !

Assuming you have adhered to the convention and defined partition #1 as the swap area then for our example disk the command would be;

     sun (ksh) # swap -a /dev/dsk/c0t1d0s1
     sun (ksh) #

In classic Unix style swap remains silent if all is well. You can confirm your swap partition is now live with swap -l;

      sun (ksh)# swap -l
      swapfile             dev  swaplo blocks   free
      /dev/dsk/c0t3d0s1   32,25      8 205624 165408
      /dev/dsk/c0t1d0s1   32,9       8 236992 236992

You now need to add it to vfstab.


We are going to make our new filesystem available under a new directory called /data. This doesn’t exist yet so we create it with ‘mkdir /data’. After editing /etc/vfstab the new entry looks like this;

/dev/dsk/c0t1d0s5 /dev/rdsk/c0t1d0s5 /data   ufs  3  yes     -

The seven fields of vfstab are;

  1. Block device – used for ‘mount’, and ‘swap’
  2. Character (raw) device – used by fsck. (for swap partitions this should be «-«)
  3. Mount point for the file system (for swap partitions ths should be «-«)
  4. Filesystem type. ‘ufs’ for a filesystem, ‘swap’ for a swap partition.
  5. fsck pass number. See below
  6. mount at boot time ? YES|NO
  7. mount options. See the manual pages for mount(1m) and mount_ufs(1m) for a full list.

After saving it, you should be able to do a ‘mount -a’ and have your new filesystem mounted under /data.. You’ll likely see some warnings about other filesystems already being mounted – these can be safely ignored