Navigating the Root Directory
This page explains how the file system is set up, and where the various pieces
of the system live.
Let's look at the root directory on a slave:
bin |
data |
etc |
initrd |
ldas_outgoing |
lib |
misc |
net |
opt |
root |
scratch |
usr |
boot |
dev |
home |
ldas |
ldcg |
lost+found |
mnt |
netdata |
proc |
sbin |
tmp |
var |
The directories bin
dev lib lost+found misc
proc root sbin tmp usr
are used in the normal Red Hat way and should be familiar to anyone doing
system administration on the beowulf.
The following directories are special:
- boot
This directory contains the kernel and files used by lilo. It also
contains an initial ram disk image that can be used to boot the system
with its root filesystem over NFS. The modules for the kernel are found
in /lib/modules/KERNELVERSION/ where
KERNELVERSION is the full version number of the kernel installed (e.g.
2.4.19-1medusa). The kernel and modules are installed as RPMS and should
be managed as such.
- data
This is where UWM's current LIGO data resides. Each slave has different
parts of the data.
- etc
This directory contains the system configuration files. A lot of the
custom RPMS that we have made (such as the UPS software) place their
config files in here.
- home
The directories search01 to search16 reside here.
- ldas
This directory contains the
LIGO Data Analysis System (LDAS) software. It is mounted from uwmlsc.
- ldcg
This directory contains the LIGO Data Computing Group (LDCG) software. It
is installed as a single RPM on each slave. There are a number of
different packages installed in the RPM. It contains software with
specific versions and patches for use with LDAS. To use this software,
add the contents of /etc/ldcg.sh or
/etc/ldcg.csh to your bash_profile and/or bashrc
or cshrc as appropriate.
- mnt
This directory is managed by automount. It contains the following virtual
mount points:
- scratch
Scratch space for users of the cluster.
- 7.3install
Files relevant to the installation process on the slaves and masters.
- backup
Files relevant to backing up important user account information. Proceed
with caution.
- ldas
This directory contains the
LIGO Data Analysis System (LDAS) software.
- ldas_outgoing
This directory contains files relevant to the the LDAS software.
- mail
This is the groups mail spool.
- floppy
A mount mount for floppies formatted with the ext2 file system.
- floppy_msdos
A mount mount for floppies formatted with the MS-DOS file system.
- cdrom
A mount mount for the CD-ROM drive for disks formatted with the ISO9660 file system.
- net
This directory is managed by automount. It contains mount points for the
root filesystem of every slave and master. The directories are named:
/net/s001 ... /net/s320 for the slaves.
/net/m001 ... /net/m003 for the master.
- opt
This directory should contain any software that is installed on each
node, but is "non standard". This includes software such as MPICH or
condor. Each package should be installed in its own sub-directory of
/opt not at the top level. Users who want to run
software in this directory may set their include and library paths
approriately.
For example MPICH resides in /opt/mpich-1.2.1/.
A user who wanted to use MPICH would add /opt/mpich-1.2.1/bin to their PATH, etc.
There should never be a directories such as lib, include
or bin directly under /opt. If these directories exist, someone has
screwed up.
- var
This directory contains several interresting sub-directories:
- /var/log/
contains the log files from a particular slave.
- /var/chroot/
contains directories that hold chrooted file systems. At the moment this
is used by BIND which runs chrooted in /var/chroot/bind/. Other programs that need to be run
chrooted should have their root be placed in here
- /var/spool/mail
is a symbolic link to /mnt/mail
The other directories under /var are used by
various operating system programs and should not be touched unless you
know what you are doing.
$Id: file_system.html,v 1.3 2003/01/07 18:14:09 kflasch Exp $