Saving Files to NFS Storage
From BCCD 3.0
Mounting the NFS Filesystem
Become Root
[bccd@mocha]>su -
The password is letmein
(or see the login splash screen for your image's root password).
Start Portmap
Portmap is a service that needs to be running to mount an NFS share.
[root@mocha]# /etc/init.d/portmap start
Make a Mount Point
Make the "mount point" on a read-write area of the BCCD system:
mkdir /mnt/rw/nfs
Mount the NFS Filesystem
Finally, mount the NFS filesystem:
mount nfs.server.com:/remote/files /mnt/rw/nfs
where nfs.server.com
is the host name of the nfs server, /remote/files
is the filesystem that the nfs server is exporting, and /mnt/rw/nfs
is where you would like the files locally mounted.
Accessing the Filesystem
Access as Root
Depending on what options the nfs server is currently running, you may or may not be able to access your files as user 'root' on the BCCD. To try this, just cd to the /mnt/rw/nfs directory and see what happens. If this works, then modify to your heart's content and skip to the next section. If it doesn't work, you will probably see an error message much like the following:
[root@mocha]# cd /mnt/rw/nfs bash: cd: nfs: Permission denied
If you do NOT get any error, chances are you are all set: log out and enjoy. Otherwise, the NFS server is probably configured with a 'root squash' option, which doesn't allow root to access any filesystems.
Access as a New User
To get around the 'root squash', you need to create a user with the same UID (user id) as you usually have when using your NFS filesystem. If you don't know what your user id is, issue this command:
[root@mocha]>ls -la /mnt/rw/
and you should see something like the following:
total 12 drwxrwxrwt 10 root root 200 Jun 3 15:01 . drwxr-xr-x 1 root root 32 Jan 1 1970 .. drwx------ 1001 1001 60 Jun 3 2004 nfs
Look for the nfs line. In the above example, the UID of the mounted nfs directory is 1001. Make a new user corresponding to the UID of the mounted nfs directory. This can be done as follows:
[root@mocha]# useradd -u 1001 username
where 1001
is your UID and username
is your username (not root, but your usual NFS username).
Now become the new user.
[root@mocha]# su - username
where username
is your username. Now cd into the NFS mounted directory and modify away!
[username@mocha]> cd /mnt/rw/nfs
Unmounting the NFS Filesystem
On a Unix-style system, drives that are mounted cannot be arbitrarilly removed. To unmount the filesystem, you will need to do a few simple things:
- Make sure that you are not currently navigating the mounted disk. A good way to do this is to issue
cd
from all of your shells, orpwd
to make sure that you don't have/mnt/rw/nfs
(or where ever it may be mounted) as part of your current working directory. - Make sure that you don't have any programs running that have been started when you had the nfs mount in your current working directory. This is uncommon, but can be frustrating when you can't seem to tell why the nfs filesystem won't unmount.
- Make sure you are root.
Once you have met these conditions, you need to unmount the disk partition.
[root@mocha:~]# umount /mnt/rw/nfs
[Note that there is no "n" in umount
. It's missing. If you find it, please let us know so that we can put it with the "e" that we found left out of /etc/resolv.conf]
That should do it!