Checking the Status of Server Machines

Sometimes one or more server machines in your cell become inaccessible due to hardware problems, software problems, or routine maintenance. During the outage, you cannot access files stored on those machines or save any changes you have made to files that are stored on those machines. (Your Cache Manager possibly has copies of the files stored locally, which you can still work with.)

To check the status of server machines, use the fs checkservers command. If a server machine has more than one network interface address (is multihomed), the Cache Manager sends the status-checking message to all of the machine's interfaces. If at least one of the server's interfaces replies, the command's output reports the machine as accessible. If there is no reply from any of the interfaces, the output reports the machine as inaccessible but displays only one of the interfaces (usually the one with the best preference rank; see Displaying Server Preference Ranks).

To check the status of different groups of server machines, combine the fs checkservers command's options as indicated:

It can take several minutes for the command shell prompt to return, because the fs command interpreter waits a timeout period before concluding that an unresponsive machine is really inaccessible. To have the command shell prompt return immediately, add the ampersand (&), which runs the fs checkservers command in the background.

To Check File Server Machine Status

Issue the fs checkservers command to check the status of file server machines.

   % fs checkservers [-cell <cell to check>] [-all]  [&]

where

-cell

Names each cell for which to check server machine status. Do not combine this argument and the -all flag.

-all

Checks the status of all server machines. Do not combine this flag and the -cell argument.

The following message indicates that all server machines replied to the Cache Manager's status-checking message:

   All servers are running.

Otherwise, a message like the following lists the inaccessible machines:

   These servers unavailable due to network or server problems: list of machines.

Example: Checking Server Machine Status

The following example checks the status of every file server machine the Cache Manager has contacted in any cell. Two machines are not responding.

   % fs checkservers -all &
   These servers unavailable due to network or server problems:
      fs1.abc.com server7.stateu.edu.