Handling Problems

This chapter tells you what to do if you have a problem using the system. You should skim this information keeping in mind that you will only need to refer to it if you actually run into a problem.

Recovering Lost Files

Restores - If you need a file restored that was deleted less than 24 hours ago, you can perform the restore yourself. Simply open a UNIX window and type cd .ckpt while in your home directory. The .ckpt directory contains 24 sub-directories (one for each of the past 24 hours), each containing a snapshot or copy of your files. You can cd into one of the hourly.## directories to look for the file you need. Once you find it, use the command cp filname ../../ to return the file to your home directory.

To restore files that have been deleted for over 24 hours, an Operator will need to pull the data off of a tape. You should submit a Help Request by sending an e-mail to help@cse.ohio-state.edu with the name of the file you need restored, the original location of the file, and the date you need it restored from. See section "Entering or Creating a Help Request" for more information. To determine which type of backup is required the operators need to know approximately the last day the file was altered. Since file restorations are time-consuming, the operators cannot restore every file requested. For example, they cannot restore files that students had in their account the previous quarter, nor files that are not needed for a class. If you can recreate the file in a reasonable amount of time (say an hour or so), you should recreate the file instead of submitting a restoration request.

For example, say you were working on a program named lab1.mod and a paper for a class named paper.txt. At some point, you accidentally save paper.txt under the name lab1.mod. Before contacting the operator, you would double-check your directory, to make sure you do not have a back-up copy of the file. XEmacs automatically saves a copy of your file as filename~ when you start to edit it. Assuming that you cannot find a recent back-up, you might then contact the operator. You will need to tell them the name of the file (account-name/lab1.mod) and when it was last changed. If you had not worked on it for the past two days, then you might tell the operator that you want a copy saved between the afternoon of October the 2nd and the morning of October the 4th. The operators could then look on the back-up tapes for those days to find a copy.

You should submit your restoration request as soon as possible after you realize the file is gone. The filer is backed up on a daily, weekly, and monthly schedule. Daily backups are kept for seven days, weekly backups are kept for a month, and monthly backups are kept for at least ten months. Daily backups only save files that have changed since the last weekly back up, and weekly backups only save files that have been changed since the last weekly back up, and weekly backups only save files that have been changed since the last monthly. Monthly backups save everything on the file server.

Since file restorations are time-consuming, the operators cannot restore certain files. The operators cannot restore files that you had in your account in a previous quarter. Files that are not needed for a class will not be restored, as a general rule. If you can recreate the file in a reasonable amount of time (say an hour or so), you should recreate the file instead of submitting a restoration request. These are guidelines and if you have special circumstances, the computing services staff may be able to make an exception.

Entering or Creating a Help Request

There will be times when you need to create a request. To do so, send email to the address help@cse.ohio-state.edu.

In the Subject, type in a brief, one line sentence summarizing the problem. For example, say the bulk feed on lj111a is constantly jamming and an operator has redirected the printer so it is no longer able to accept print jobs. You should have a Subject of something like ``The printer lj111a is constantly jamming''.

In the body of the message, enter the full request. Please try to be clear but concise.

Note: If you have something sensitive to include in the request (such as private information like a social security number), be sure to put the word ``PRIVATE''--in all capital letters--in the Subject header. That will prevent the request from being seen by random users browsing the help system.

You will get a copy of the mail that is used to generate the request. Keep that message until the problem is resolved.

Adding To Existing Requests

Remember the mail you got in response to your request? In order to add to an existing request, the best thing to do is reply to that message that you created. That will ensure that the new information is added to the right ticket.

Watching Requests

In order to see the status of a request, you may visit the help system web site at http://help.cse.ohio-state.edu/.

Disk Quotas

The disk quota system helps manage the use of disk space more automatically and effectively. It guarantees that each user will be able to use up to a specified amount of disk space (defined by their soft quota, see below).

What They Are and How They Work

This quota system defines two limits for each user: a soft quota and a hard quota. The soft quota is the maximum amount of disk space allocated to a user. For example, one might have a soft quota of 500 kilobytes (Kb). That means that the user is guaranteed access to 500 Kb of space but should not exceed this limit.

The hard quota is larger than or equal to the soft quota. It is the maximum amount of space that a user can access before his account usage will be affected. This extra space constitutes an ``emergency buffer'' for temporary use only when exceeding the soft quota is unavoidable.

One can exceed his soft quota for at most two days, but it is not possible to exceed the hard quota and retain full account functionality. If the hard quota is exceeded, account operations will be limited to deleting files. This means that saving files during editing, copying files, compressing files--any operation which requires more disk space, will not be possible. If the soft quota is exceeded for more than two days, your account will be restricted as in the case of a hard quota violation.

Usage Warnings

The program quota can be used check your disk usage and quota restrictions. If you are using the default login files, this program is executed during login and displays warnings whenever you exceed a quota:

Over disk quota on /home/0, remove 95K within 2.0 weeks

If you do not use the default login files, you can edit your .login file and add the command

quota -v

which will perform the check during every login. Simply executing quota -v will display your quota information.

Default Quota Settings for Accounts

Type	Quota
CSE Tenure-Track Faculty	4GB
CSE Staff/Instructors	1GB
Graduate Students	800 MB
Undergraduate Majors	300 MB
Undergraduate non-majors	30 MB
Collaborative guests	``0'' MB

Conserving Disk Space

Your disk space can be more effectively utilized by removing all non-essential files and gziping or comprssing essential ones.

Non-essential Files

There are several types of temporary files which are commonly created during file editing and program compilation. When editing with XEmacs, backup files and autosave files such as prog1.c~ and #message# are created. If you have a current version of the file, you should remove these backups. See "XEmacs backup files" for more information concerning backup files.

During program compilation, intermediate files are created which are no longer needed when program modification is complete. Such files can include object files (.o extension) and symbol table files (.sym extension). During a given programming session, these intermediate files should not be deleted because they facilitate separate compilation. However, before logging off, you should remove all of them because they can be easily recreated. In addition to these temporary files, executable files which you have created should be deleted.

Determining which remaining files are non-essential is subjective. However, old mail, news articles, and the like are usually good candidates for removal.

Archiving/Compressing Files

It is possible to modify files so that they take less space. As described earlier the two primary ways to do this are tape archiving and file compression. Files can be stored in your account or on an external tape in archived form. See the section gzip for details on compressing files.

Note: if for some reason you suddenly are over quota, a core file may be the culprit. Whenever a process crashes, it will often times do a core dump in an attempt to save data. Whenever a process crashes and/or you suddenly go over quota, do an ls -a in all your directories and look for a core file and remove it using rm.

Also: Netscape can eat up a lot of memory, especially when you view graphics. One way to prevent going over quota when running Netscape is to lower the cache in Netscape. To do so, in your Netscape browser window go to the ``options'' pull down menu and select ``Network Preference.'' Next, change the ``Disk Cache'' and the ``Memorey Cache'' values to ``0''.