User`s guide

Troubleshooting and Debugging
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how to start it and how to test connectivity, see “Start Admin Center” and “Test
Connectivity” in the MATLAB Distributed Computing Server documentation.
Detailed instructions for other methods of diagnosing connection problems between the
client and MJS can be found in some of the Bug Reports listed on the MathWorks Web
site.
The following sections can help you identify the general nature of some connection
problems.
Client Cannot See the MJS
If you cannot locate or connect to your MJS with parcluster, the most likely reasons
for this failure are:
• The MJS is currently not running.
• Firewalls do not allow traffic from the client to the MJS.
• The client and the MJS are not running the same version of the software.
• The client and the MJS cannot resolve each other’s short hostnames.
• The MJS is using a nondefault BASE_PORT setting as defined in the mdce_def file,
and the Host property in the cluster profile does not specify this port.
MJS Cannot See the Client
If a warning message says that the MJS cannot open a TCP connection to the client
computer, the most likely reasons for this are
• Firewalls do not allow traffic from the MJS to the client.
• The MJS cannot resolve the short hostname of the client computer. Use pctconfig to
change the hostname that the MJS will use for contacting the client.
SFTP Error: Received Message Too Long
The example code for generic schedulers with non-shared file systems contacts an sftp
server to handle the file transfer to and from the cluster’s file system. This use of sftp is
subject to all the normal sftp vulnerabilities. One problem that can occur results in an
error message similar to this:
Caused by:
Error using ==> RemoteClusterAccess>RemoteClusterAccess.waitForChoreToFinishOrError at 780
The following errors occurred in the
com.mathworks.toolbox.distcomp.clusteraccess.UploadFilesChore: