Tuxedo Interview Questions - 2

Q. How are TUXEDO service statistics activated?
A. Reporting can be turned on using the -r server option specified in the CLOPT parameter. The statistics are logged to standard error, so we typically use the -e server option to redirect stderr to some other filename rather than the default $APPDIR/stderr. The stats file produced becomes input to the Tuxedo reporting facility, txrpt. Cool stuff.

Q. In a TUXEDO application, calling a service using tpacall() (asynchronous request) makes the service go faster than when using tpcall(): True or False?
A. No, it doesn't. The service will not execute any faster, but the call to tpacall will return to the caller faster than tpcall. That's because tpcall performs a tpacall with an immediate call to tpgetrply. The service behaves the same, and does not realize if it is being requested asynchronously or synchronously.

Q. Legacy database Y is not XA-compliant (naturally), therefore I can't access it via TUXEDO:
A. Not true. TUXEDO can access any resource -- with XA or without.

Q. In a TUXEDO MP application, what happens if you don't start up tlisten on the MASTER node?
A. The application will run but a slave node cannot assume administrative responsibility You get a warning but everything works. If, however you migrate to a backup node you will have problems bringing up servers on the master. Nothing special...unless your backup master takes control as master and at some point needs to boot the original master machine.

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Tuxedo Interview Questions - 1

Q. What does TUXEDO mean?
A. Transactions for UniX, Enhanced for Distributed Operation

Q. And what exactly is TUXEDO?
A. TUXEDO is at least three things:
It's middleware :- it relays requests and responses between client and server processes (with or without transactions).
It's a Transaction Processing (TP) monitor :- it begins, terminates, and monitors transactions on behalf of client and server processes.
It's a Distributed TP monitor (DTP) :- it allows the transaction participants to be located on different machines or associated with different databases
Many people who are tired of low-level networking (streams, sockets, daemons etc.) use TUXEDO as their software communication infrastructure.

Q. Which companies owned TUXEDO before BEA?
A. AT&T, USL, Novell.

Q. What's the TUXEDO 'buddy' mechanism?
A. The DBBL keeps the BBL up, the BBL keeps the DBBL (and all other servers) up.

Q. How can I test my services without having to write a variety of client driver modules?
A. Tuxedo provides a utility driver client (ud/ud32) which can serve as a great test driver. The ud program can drive simple interaction and can be configured to drive complex, multi-call interaction. It's great to use in scripts to drive performance tests. It also comes in a workstation flavor (wud/wud32). Caveat - your services must accept FML/FML32 input to use ud. If your services don't accept FML input, consider modifying them to do so.

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