Daren Matthews

This post describes typical message exchange sequence for a client connecting to a user level server, opening a file, reading its data, closing the file, and disconnecting from the server. Opportunistic Locking (Oplocks) are also explained.

You can also refer tothis capture: Download smbtorture from Wireshark Wiki to further understand the SMB dialogues. The capture was made using the Samba4 smbtorture suite, against a Windows Vista beta2 server. Read more…

Instructional video courtesy of blindhog.net:

http://www.blindhog.net/tutorials/dynagen-linux-install.htm

A  nice little introduction to network monitoring (provided by my employer – registration required for obtaining the free download). This book does lean slightly towards using Cascade products to provide monitoring, troubleshooting and analytics – BUT I’m happy to say that it does remain a nice little read for anyone who has an interest in network monitoring. Read more…

Both the ~/.bashrc and ~/.bash_profile are scripts that might be executed when bash is invoked. The ~/.bashrc file gets executed when you run bash using an interactive shell that is not a login shell. The ~/.bash_profile only gets executed during a login shell. What does this all mean? Read more…

RFC 2597 defines four Assured Forwarding groups, denoted by the letters “AF” followed by two digits: Read more…

These failure codes are the original error codes from the Kerberos RFC 1510 Read more…

When a client connects to a server using SMB it sends a “Negotiate Protocol Request”.  In response to this, the server replies with a “Negotiate Protocol Response”.  This response reveals whether SMB signing is enabled and whether it is required at the client, the server, or both. Read more…

These YouTube Videos show how simple it is to create Virtualized and Para-Virtualised Guest Operating Systems using Xen Hypervisor Read more…

Matching TCP traffic with particular flag combinations can be a useful way of examining TCP conversations.  Refer to the TCP State Machine to understand the context of these flags: Read more…