Category Archives: Computers
Outlook / Exchange Error: Network Problems or the Microsoft Exchange Server Computer is Down for Maintenance

There are tons of posts about this subject, but none of them offered the very simple solution that worked for me: Make sure the Microsoft Exchange System Attendant is running on the mailbox server. We had a catastrophic crash of a VM host, on which our Exchange 2013 server was running as a guest. Everything seemed to come back up just fine, and all Outlook users were back online with Exchange, except for two. One user was running Outlook 2016 like the rest of the org, but one was running Outlook 2007 (don’t ask). They seemed to have nothing in common, but they both were throwing errors that network problems were preventing communication with the Exchange server. I did all … Continue reading
Clone a Dynamic Disk to a New SSD in Windows 10

This is partially just for my own reference, so I don’t have to go down this rabbit hole again. (But I hope it helps you, too!) The Situation I wanted to upgrade the LITE-ON 256GB SSD in my trusty ol’ Lenovo X1 Carbon laptop to a snazzy new Samsung 960 EVO 2TB drive. I have a version of Acronis that came with a Crucial (or Kingston?) SSD, which has worked great in the past. The problem? There was a system reserved partition at the very end of the disk, and Acronis therefore would not proportionally scale the OS partition to fill the disk; It would only scale that system reserved partition. In a moment of errant stupidity, I said, “Ah-hah! … Continue reading
Redundant VPN Tunnels via Different ISPs

Intro My friends will tell you that I’m obsessed with redundancy, both in life and in I.T. At home I have two main internet connections, via Altice Optimum (“cable”) and Verizon FiOS. They’re both relatively high bandwidth, and are connected to my two core routers that operate in an active/passive configuration. Basically this: O——O +——–+ / \ | |————/ O +——————+——————–| Core | / / | Optimum Router | | Router |———-O / +——————+\ ______________| 01 | \ O \ / | |————O \ \ / +——–+ / \ X Keepalived | / Various O / \ Heartbeat | O Networks / / \ +——–+ \ O +——————+/ \_____________| |———–\ \ | FiOS Router | | Core | \ O … Continue reading
RAID HDD TCO Calculator (Total Cost of Ownership)

A while back I created a HDD TCO worksheet showing the relative costs of certain drives in no real context. This spreadsheet aims to calculate the total cost of ownership for a RAID array, which is a much more involved affair. https://docs.google.com/spreadsheets/d/1dM2vO08gmX3VwYyJtTE5D1Gu75TTU-nUW95j1_DVx8c/ That’s a read-only version, but you can easily make your own copy to play with: If you have a Google account and are logged in, you can just hit File -> Make a Copy.. to save it to your own Google Drive. If you hate Google sniffing into your private affairs, you can hit File -> Download As and grab a copy in the format of your choice. I hope I’ve provided enough of an explanation as to … Continue reading
Yes, the Dell Compellent SC220 Chassis AND Drives are Generic!

I found a great deal on eBay. A Dell Compellent SC220 chassis filled with 24 x 600GB 10K SAS disks for $350 including shipping. Obviously if you’re reading this years later that will seem like a terrible price, but as of now 600GB SAS drives are selling for about $30 each (used). So it’s roughly $720 worth of drives alone. The SC220 is basically an MD1220 in sheep’s clothing (though sheep are generally naked so who knows), and those are selling for about $120. Like I said, a great deal! But there was one question that needed answering: Did the Dell-branded Compellent HDDs have some kind of special firmware that rendered them useless with a standard RAID or JBOD controller? … Continue reading
Apparently myisamchk Doesn’t Understand 2-Digit Numbers (MySQL)

myisamchk If you’re reading this, it’s probably because you’re trying to run myisamchk on a large table and you want to set the –sort_buffer_size to some large value. That’s advisable, of course. However, it seems that some versions of MySQL don’t understand a 2-digit value for that parameter. I was trying to do the following: myisamchk -f -r –update-state –key_buffer_size=4G –sort_buffer_size=16G –read_buffer_size=32M –write_buffer_size=32M /var/sql/myisam-temp/mastersitedb/applicants_master_search – recovering (with sort) MyISAM-table ‘/var/sql/myisam-temp/mastersitedb/applicants_master_search’ Data records: 0 – Fixing index 1 myisamchk: error: myisam_sort_buffer_size is too small MyISAM-table ‘/var/sql/myisam-temp/mastersitedb/applicants_master_search’ is not fixed because of errors Try fixing it by using the –safe-recover (-o), the –force (-f) option or by not using the –quick (-q) flag If you’re getting an error like that, try using … Continue reading
Disregard: Sealed Lead Acid Battery Longevity Log

Edit: ACTUALLY, NEVERMIND It’s now June of 2020, and I figure it’s time to put a big “disregard” in the title of this post. While my objectives were indeed grand, there’s a fundamental flaw in my methodology: Most of the UPSes in question do not perform battery self-tests. As such, I really only find out about bad batteries when there’s an actual power failure. And those happen very inconsistently, and infrequently. (Which is good for me overall, but bad for this “log”.) For example, my power just flickered briefly and one UPS shut down as soon as the power went off. The batteries were dated as replaced on 2017-12-10. However, that UPS survived the last power outage some months ago, … Continue reading
Amazon Echo Look – Teardown

The Echo Look I’m working on a full review-type-thing of the Look, but who really cares about that? I’m sure people will want to see the insides of it, though. The most interesting two things on it are an Intel RealSense SR300 module (minus its visible light camera), and what’s basically a full Intel PC motherboard. In fact, here are the main specs: Intel Atom x5-Z8350 (SR2KT) @ 1.44Ghz (1.91Ghz burst) 8GB Samsung eMMC Flash NAND Storage 8GB Elpida LPDDR3 RAM Broadcom 802.11ac + 802.11b/g/a/n + Bluetooth (Not sure of the version) The hardware is fantastically made and well put together, and overall is very clever considering they stuffed all of it into a diminutive cylinder! The Reassembly I did … Continue reading
ZeroFiller: Nearly Fill Up a Disk with Zeroes for Snapshot Backups

ZeroFiller (for Windows!) This might be a relatively niche utility, but I figured I’d share it because it might help someone in the same situation. File Version Description ZeroFiller-v0.8-20171023.zip v0.8a2017-10-23 The ZeroFiller executable only (requires .NET 4.5.2) ZeroFiller-src-0.8a-20171023.zip v0.8a2017-10-23 The ZeroFiller source code (requires >= Visual Studio 2017, probably) Backups I run a lot of VMs and I’m a bit obsessed with backups. I do high-level backups (meaning files, DB data, configs, etc.), as well as low-level backups of the actual VM disk images. The raw virtual disks get snapshotted on the host system, then the snapshot’s raw data is backed up using dd, gzip, and rsync. It’s not fancy, and it basically grabs the machine in a crashed state … Continue reading