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More on virtual debugging with record/replay

More from VMware’s Slava Malyugin: Debugging the virtual world.: Configuring application debugging with Record/Replay.

In my previous article I explained how to debug processes running in Ubuntu 7.04 VM using Record/Replay technology built into VMware Workstation 6.0.1. This article tells how to use Record/Replay debugging with different distributions of Linux.

When
debugging an application using Record/Replay, you need to run the
debugger on the Host (outside of Virtual Machine). The reason for this
is obvious – if the debugger runs inside the Virtual Machine, it will
disturb the execution of the VM and you will not get 100% determinism.
The downside of running the debugger outside of the VM is that it
cannot use kernel services to debug processes.

We solved this
problem by teaching our debugger how to implement process-level
debugging by traversing Linux kernel data structures. Since the Linux
kernel is evolving rapidly, the format of these data structures changes
quite frequently. This is why we require users to tell us the offsets
of some kernel data structures with the "monitor linuxoffsets" command. …

Note that these scripts and Record/Replay feature in the WS6.0.1 are
not officially supported by VMware. If you have questions or
suggestions, the best place to express them is our forum. Thank you.