COMMON LABS IN CSA:   
This page contains information for student admins and also for common lab users.



LAB Information:
Lab Name
 LITEC CL2
 CL1
No. Machines
 16
 6
 22
Configuration
 HP Workstations,
 Intel Xeon dual cores
 Pentium 4 Dual Cores
 Sun Thin Clients
OS:
 Ubuntu
 Ubuntu
 Red Hat
Machine Names
 hp1,hp2,hp3,hp4,...,hp16
 vega, apus, sirius, procyon, algol, phobos
IP range:
 10.192.20.16 to 10.192.20.31
 10.192.13.12 to 10.192.13.17
 10.192.13.38


SERVER Information:
server name:
 pingu
 csastorage
 claccess
 backup
IP
 10.192.12.87
 10.192.13.11
 10.192.12.88
 10.192.12.5
OS:
 Debian
 Debain
 Debian
 Debian
Purpose:
 1. LDAP
2. webmail
 NFS server
 1. Outside IISc
Network  Access,
2. alpine
 1. File Backup
2. CSA wiki

Location:
 CL2
 CL1
 CL2
 CL2

Printer Servers:
10.192.12.61, euler: CL2
10.192.20.15, athena; LITEC  


Common Administration Information:


LDAP
 Authentication System:
1. Users can login using same username and password into any of the common lab machines.
2. This same username serves as the official CSA email ID.
3. pingu is configured as the LDAP server.
4. LDAP commands are used to modify user passwords, home directory, or any other details on pingu.
5. All the scripts related to LDAP are stored in pingu: /home/super/ 2010/
NFS
 Network File Share system
1. User home directories are all stored on the csastorage server.
2. All the other machines remote mount the home directories from csastorage.
3. csastorage uses NFS to share the home directories.
4. Maximum of 4GB space is allocated to any home directory.
autofs
 automatic mounting
1. All the machines except the csastorage server use autofs to automatically remote mount the home directories from csastorage server.
2. All the common lab machines have autofs setup. Even pingu and claccess have autofs.
3. autofs remote mounts the home directory shared by csastorage through NFS, at bootup.
crontab,
rsync
 crontab and rsync are used to setup the backup on the csastorage server.
1. rsync is run from the csastorage to backup all user home directories.
2. rsync is an incremental copy program. It copies only the changes since the last backup.
3. Source of backup is csastorage server and destination is backup server.
4. rsync is run daily at 3am.
5. crontab is used to schedule rsync daily at 3am
6. So, the csastorage server has scheduled the rsync using crontab.
outside
IISc network
 1. Except claccess, we cannot ssh to any other common lab machines
2. ssh <username>@login.claccess.csa.iisc.ernet.in
3. Outside IISc IP for claccess: 144.16.67.22
webmail
 1. The folder /var/mail/ on pingu.
2. All the user inbox mails are stored in this folder, with the filename as the respective username.
3. The maximum size of the INBOX is 129MB.
4. If the Inbox exceeds the quota, all the inbox mails are blocked.
5. If your inbox quota is filled and someone sends you an email, the mail will bounce back and he will get a delivery failure
6. We can create folders and move our mails from the INBOX to these folders. In such cases the new folders are created in the respective home directories.
7. If we move mails from inbox to other folders, then the INBOX does not retain a copy of the mail. The mail is deleted from INBOX and copied to the new folder.
.forward
 1. The file ".forward" can be used to forward incoming mails to other email accounts
2. Users can use .forward to forward all mails from CSA webmail to any other email account
3. Just create a file named ".forward" in your home directory. And write the email you want the mails to be forwarded to in that file.
5." .forward" does not retain any local copies of the mail.
6. You cannot add the clmail email id in .forward as it will create loops. This will cause mails to bounce back without being delivered to you.
4. Look up on the net advanced uses of .forward
Backup
 The folder /b-drive/csastore on backup server is the destination where all the backup is taken.





Installing package on all common lab machines.
1. Even though the login and home directories are shared via network, all the common lab machines have a local installation of Ubuntu.
2. So, we have to install packages on each machine individually.
3. Check the pingu: /root/installScript/scripts/ folder. Some python and shell script are written which remotely logs into all common lab machines and installs the required packages.

Setting up a new client, in common labs:
1. Login into any of common lab machiens, each machine has a folder:
/home/super/install-new/
2. After installing a new ubuntu just run the scripts in that folder, in the order: firstBoot.sh, afterUpgrade.sh
3. You may need to change some files from time to time.

Common Lab Machines Not working, What to Do?
Possible Problems:
1. Check whether none of the common lab machines are not working. It might be a local machine problem.
2. If all the machines are not working then the problem is with the server or the network.
3. If your login cannot be authenticated that means pingu is not working.
4. But if the machine hangs after authenticating you, that means the file server is down.
5. Best option is to try to ping the servers from some working machine.


Problem With servers:
1. If the problem cannot be solved trivially, or is something that has not been faced earlier, check the logs.
2. /var/log/ stores all kinds of logs.
3. If any user faces any problem with logging in or checking mails check the /var/log/mail.err log.
4. If there is some local problem check the /var/log/messages, /var/log/dmesg, /var/log/syslog, etc