Accessing Central Filesystems from CLASSE Linux Boxes

CLASSE provides several network accessible fileystems to our linux and unix systems using NFS. For a comprehensive list of available filesystems, please see https://www.classe.cornell.edu/private/computing/filesystems.html .

To check if your file system is currently being backed up, see BackupSchedule. To request changes to this schedule, please open a ServiceRequest.

Access

When accessing NFS filesystems from Linux, you must always specify /nfs/ or /home/ as the first part of the name. That tells automount to access the file server which has the file and to mount the appropriate filesystem so it is available on the computer where your program is running.

NFS file systems are automounted as needed, so you must specify the full path of the share you wish to access. For example, to access the central CLASSE user disk, you must specify /nfs/user/ .

Recommendations

As with all centralized services, you will occasionally see delays accessing NFS filesystems when the filesystem or the server they reside on become overloaded or unavailable. Please follow these recommendations for minimizing the effect of these delays:

1. If your login scripts reference a network filesystem, you may be unable to login when that filesystem is unavailable. Instead, define unique commands so you can invoke those initializations individually.
2. If you have links in the root level of your home directory that point to nfs filesystems, you may be unable to login when any of those filesystems are unavailable. All such softlinks should be in a subdirectory so they won't be searched by default.
3. Please check your PATH definition to make sure that the local system directories (e.g. /bin & /usr/bin ) are searched before any nfs mounted file systems. If nfs filesystems are first,
   • delays will be felt whenever you attempt to execute any command: the nfs filesystems will be searched first, usually unsuccessfully
   • your session will hang if any of the nfs filesystems are unavailable
   • the nfs filesystem will be unnecessarily mounted whenever you attempt to execute any command, causing additional load on the servers
4. If you have . ( often called "dot", which means "current default directory") or your home directory (or wherever else you keep programs) first in your PATH, verify that you do not have any softlinks in those directories which point to other nfs mounted filesystems. All such softlinks should be in a subdirectory so they won't be searched by default.