Congratulations to Duo Security, which announced that it is to be acquired by Cisco Systems for $2.35b. This is a great outcome for all involved, and I'm very proud of what the team has accomplished.

I worked with Duo for about three years, initially as an advisor and ultimately as Chief Operating Officer running Sales, Marketing, Products, Engineering and Services. I helped grow the company from around $7m in Annual Recurring Revenue (ARR) to about $100m. The company has continued to grow to 700 employees, 12,000 customers and revenues that I estimate could exceed $200m ARR by year end, based on prior published numbers.

Duo is the fastest growing company I've been a …

A special extended edition of Tech Messages for 2011-09-21 through 2012-05-11:

• Understanding Linux CPU Load - when should you be worried?
• Performance Testing - Load Balancer SSL Stress Testing
  This is a great simple test. Thanks, Corey!
• Mosh: the mobile shell
• Twitter open sources its MySQL secret sauce
• Lab Overview
  This guy is serious about his lab!

A special extended edition of Tech Messages for 2011-08-31 through 2011-09-21:

• Lab Overview
  This guy is serious about his lab!
• Throughput
  All sorts of useful information here. My favorite is the first table which includes bandwidth and packet throughput for different kids of circuits.
• Must see: 5 Steps to Scaling MongoDB (Or Any DB) in 8 Minutes
  These tips are relevant no matter what database system you are using.
• Understanding and …

Couchbase raises $14m. AppFog raises $8m. Much ado about Percona Live MySQL Conference and Expo. And more.

# Couchbase raised $14m in series C funding for its NoSQL database.

# AppFog raised $8m series B funding for its PHP-based platform-as-a-service.

# Percona announced its plans to host a Percona Live MySQL Conference and Expo on April 10-12, effectively replacing the O’Reilly MySQL Conference and Expo.

# The announcement sparked some rumblings of discomfort around the MySQL community with Giuseppe Maxia and …

A special extended edition of Tech Messages for 2011-01-12 through 2011-01-15:

• Hg Init: a Mercurial tutorial by Joel Spolsky
  An introduction to Mercurial (hg) by Joel Spolsky. Includes a special introductory chapter for Subversion users.
• lessfs | Open source data de-duplication
  Open source filesystem with de-duplication.
• UCS B-Series and C-Series Servers Log Memory Errors due to Intel 5600 Erratum Issue
  On a subset of Intel Xeon 5600 series processors, during packet C6 transitions, CPU circuit marginality or internal signaling noise in the may lead to an invalid memory DRAM state, system hang, reboot, memory ECC errors or unpredictable system behavior. This could …

A special extended edition of Tech Messages for 2010-12-22 through 2011-01-04:

• WS-C3560V2-XXXX-X, WS-C3750V2-XXXX-X Series RPS cover and rare power reset – Replacement Recommended
  The RPS cover for wall-mount of the Acc Kits in the BOM was not correct; it should be 22P instead of 14P. The issue is a safety issue for those who choose to wall-mount the RPS. It's found on WK48P/NZ48P that the magjack connector's shielding were short to the test via 2.5v to ground. Adding capton tape underneath Belfuse/Pulse connector to avoid the short via ECO as a short term solution will respin PWB to correct issue.
• WordPress › 3.0.4 Important Security Update
  Time to update!
• …

A special extended edition of Tech Messages for 2010-12-14 through 2010-12-21:

• Cisco IOS Hints and Tricks: IOS HTTP client sets Host: field to IP address
  Still annoying…
• ACL IP Options Selective Drop – Cisco Systems
  Most networks do not make use of IP options. You can drop packets that contain options with the "ip option drop" global configuration command.
• Which loads faster?
  This tool has it's usefulness. It's especially nice to compare your site to similar sites and see what you can do to improve things.

…

In a test lab, we ran into a situation where the connection between our Cisco Access Registrar (AAA) server and MySQL server was timing out. This forced the server to reconnect and resulted in the following errors: name/radius/1 Error Server 0 ODBC client (DataSource 'my_odbc', Connection 8): SQLExecute failed: SQLState:08S01 NativeError:2006 ErrorText:[MySQL][ODBC 3.51 Driver][mysqld-5.0.21-log] MySQL […]

I have just returned from holiday and while it’s not normal reading during some of my spare time I managed to read a couple of books on IPv6 I’d recently bought to get me up to scratch and refresh my memory on the topic.

These books are:

• Deploying IPv6 Networks, by Cisco
• Understanding IPv6, Second Edition by Microsoft

The first book is quite good, and while a little old provided a good solid background for me on the subject. A lot of the information was not relevant to my interest in setting up a networked SOHO network but that’s not really a problem. The background was interesting.

The second book was a bit of a mistake. I’d ordered it as it was a …

A special extended edition of Tech Messages for 2010-04-29 through 2010-05-14:

• PowerDNS
  DNS server supporting a variety of backends including BIND-style configuration files and relational databases. Also supports providing different answers based on a requester's geographic location.
• Updated - UMPIRE Archived -- ESR or uBR PRE2 Unable To Read PCMCIA ATA Flash Disk - Data Loss or System Boot Hang - Replace Flash Card
  The PCMCIA ATA Flash Disks used in specific Cisco products may contain a Manufacturing defect which reduces reliability of the Flash device. PRE2 cards used both in the Cisco ESR10000 and uBR10000 platforms that contain a suspect Flash device may not be able to access stored files on disk 0/1. The router may …