OSI/FTAM Programming Guide

FTAM Application Management
HP NonStop OSI/FTAM Programming Guide—528612-001
6-4
Troubleshooting and Tuning
associations and connections. Check and verify all previous work performed using the
NonStop initiator, correct inappropriate file states left from the component failure, and
proceed according to your application’s needs.
The process of verifying work performed before a hardware or software component
failure and recovering from unknown file states is different for every application. The
main recovery strategies depend on the type of activity in progress during component
failure:
•
Reading from a file
•
Writing to a file that your application created
•
Writing to a file that already existed
In the case of reading a file, recovery depends on the type of file being read, how the
program uses NonStop FTAM access capabilities, and how the file was handled when
the component failed. For instance, if the application was reading an FTAM-2 file when
a line failed, the application might be able to reestablish the association and resume
reading at the point where it was interrupted. If it was reading an FTAM-1 or FTAM-3
file, it must start over.
In the case of writing to a file, you should probably consider the file unusable. If you
created the original file, the best recovery might be to delete the unusable file and
recreate it. If you were writing to a file that you did not create and whose contents you
cannot retrieve—from a file backup, for example—it might be possible to recover with
the help of someone knowledgeable about the particular FTAM responder and its host
system. In general, it is best to keep a backup of any remote FTAM file you intend to
extend or update.
Troubleshooting and Tuning
This subsection describes the tools to use to troubleshoot and tune your applications
and offers some approaches to handling application problems.
Tools
The following tools can assist you in debugging, troubleshooting, and tuning
applications:
•
Inspect
•
SCF
•
PTrace
•
EMS
The Inspect utility is a symbolic debugger that helps you identify and correct
programming errors. If you set up your development environment to create a
saveabend file in the case of failure, then if the program abends, you can use Inspect
to read the saveabend file. Inspect is also useful in other ways, such as debugging