Category Archives: Tech Notes

Vcenter Host Agent Pre-Upgrade Checker Problem

I’m attempting to upgrade a vSphere 4 to vSphere 5 Enterprise Plus installation. Just a real simple out of the box install. So I run the Vcenter Host Agent Pre-Upgrade Checker.  Simple enough. But it fails connecting to the database with a “failed to connect to database for user…” error. and “Look at the log file for more details”

Sigh…. Got me.  I know I got my credentials correct. So I do a web search, can’t find anything relevant.

So on a hunch, I just browse the CD and run Autorun with elevated privs (right click, “run as administrator”) and then it worked fine.



Installing MS-SQL Express for those not familiar with it

First of all, it’s really stupid I have to write a blog post on how to install the free Microsoft SQL express package, but it just isn’t that easy to do.  It’s nice they give it away for free for people like me to learn it all, but they assume you already know it in the limited instructions you are given.  The big problem is, there are a ton of pre-requisites that — if not already installed, will fail the installation and leave your install in a bad shape.  For example…. this lovely error:

An installation package for the product Microsoft SQL Server Native Client cannot be found. Try the installation again using a valid copy of the installation package ’sqlncli.msi’

Continue reading Installing MS-SQL Express for those not familiar with it

Prepaid U.S. Mobile Phone Howto for U.S. Visitors

This is a guide to how to get a prepaid phone that works in the United States if you plan to visit here.  Information about how to do this is hard to find because the phone companies don’t want you to just use a phone for a week or so and toss it basically.   I had similar difficulties getting a prepaid phone in UK for my trips there, but I’ll warn you, this is much more of a hassle.

Continue reading Prepaid U.S. Mobile Phone Howto for U.S. Visitors

Installing Diablo 2 on an Intel Mac

Back in the day (2000-2003) I played Diablo 2 — a lot.   A bit of nostalgia and the upcoming release of Diablo 3 meant it was time to give it another shot — but I couldn’t find my CDs anywhere. No problem, I went out and purchased the Diablo 2 Battle Chest which includes the original game plus the expansion pack — Lord of Destruction.

But would it work on my Intel-based Mac.  My backup plan was to install it on an old PC, but ideally I wanted it to work on my Mac.  There’s a few roadblocks to that plan though.  1) It was written for the old Mac OS, not “OS X” which is based on Unix.  It was also written to run on a different processor, not the Intel I have in my Mac. It was a bit of a hassle to get it working, and tech notes on how to do so were lacking, but in the end it works. You just can’t expect to pull out the CDs from the box and get it working though.

This blog entry is meant to document first how to do it, then the pitfalls I hit along the way.

Continue reading Installing Diablo 2 on an Intel Mac

Removing backups from Apple’s Time Machine

Apple’s Time Capsule is a neat device that provides both wireless access, router functions, and a hard drive for doing automated backups from one or more Macs in the same network.

It’s very easy to use and “just works.” If it runs short on disk space it starts to automatically trim the oldest backups automatically. No intervention needed.

But ease of use often means functionality can suffer, and in one area that this is true with Time Capsule and Time Machine is when it comes time to add another machine to it and there’s not enough space on it to do the first backup.

Which is what happened to me. I purchased a new Mac and wanted to add it to my Time Capsule without reformatting it and removing all my old backups from the two other computers on it.   Pruning it manually is a bit of a bear.  Hence this blog post.

Continue reading Removing backups from Apple’s Time Machine

Using the Linksys SPA-3102 as a VOIP ATA

In other blog entries I’ve been discussing a larger project of setting up a personal Voice over IP (VOIP) Asterisk server using the Linksys SPA-3102 VOIP gateway device.

An ATA (Analog Telephone Adapter) allows one to use old fashioned phones on a voice over IP network, or you can just use IP phones. An ATA like the SPA-3102  does not have to connect to an Asterisk PBX though. In a simple form, it can connect to any SIP VOIP provider for cheap Internet calls.   This is the same idea as other Internet phone plans like Vonage, Comcast, and Verizon, but you pay for only what you use, which can be as low as $0.00 a month.

Continue reading Using the Linksys SPA-3102 as a VOIP ATA

Getting around Comcast port 25 block

Comcast started blocking outbound port 25 on my cable modem yesterday. I can understand why — it stops a lot of infected machines from spamming the world. But it also broke the ability of my security webcam from sending me pictures to my server whenever it detects movement, and the cam firmware has no option to use the alternate authenticated port 587.

So this blog entry talks about how I got around the port 25 block so my webcam can continue to email images.

Continue reading Getting around Comcast port 25 block

Importing a mirrored disk pair into new Windows 2003 Server

At home I run a Windows 2003 R2 Server configured for Active Directory and file service for my couple of computers in the house. Way overkill but I originally did it for the learning experience and now maintain it so I don’t lose touch. Since I’m in management now, I don’t do much “real work” and always worry about forgetting how all this works. Continue reading Importing a mirrored disk pair into new Windows 2003 Server

Personal VOIP/PBX using Asterisk, part 2

This is part two of my series on how to set up an asterisk server for home use on a Linode VPS — but is applicable to any host that doesn’t have additional hardware telephony devices installed in the server. Please refer to Part 1 for how to set up the dummy timing module.

Also, before continuing, please read my little sidebar post about IP telephony codecs. Most specifically the part on adding iLBC codec to the asterisk config. Then “read more” below for the rest of this post.

Continue reading Personal VOIP/PBX using Asterisk, part 2

IP Telephony Codecs

My first stumbling block when installing and trying to get Asterisk PBX working were the codecs and mismatching. If both ends of a connection can’t negotiate the same codec, the call won’t complete.

I grabbed the recommended asterisk config for gizmo5 and when attempting to place a call to my gizmo call-in number which should have landed it into my PBX I got the following errors and it disconnected:

[Jan 14 01:40:20] WARNING[23334] channel.c: Unable to find a codec translation path from 0x400 (ilbc) to 0x4 (ulaw)
[Jan 14 01:40:21] WARNING[23334] channel.c: Unable to find a codec translation path from 0x400 (ilbc) to 0x2 (gsm)

When trying to determine what went wrong, I found that ilbc is no longer part of Asterisk config, and ulaw is actually G.711 using the  µ-law algorithm. I also found that one can add iLBC codec to Asterisk by agreeing to a license agreement and running a script.

So hence this blog post, so I can document what I’ve learned and hopefully prevent someone else from having same frustrations.

Continue reading IP Telephony Codecs