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Finding the most expensive recent SQL queries on SQL Server

Unknownbolt | 2017-11-02

Mostly a note to self, original source here. SELECT TOP 10 SUBSTRING(qt.TEXT, (qs.statement_start_offset/2)+1, ((CASE qs.statement_end_offset WHEN -1 THEN DATALENGTH(qt.TEXT) ELSE qs.statement_end_offset END – qs.statement_start_offset)/2)+1), qs.execution_count, qs.total_logical_reads, qs.last_logical_reads, qs.total_logical_writes, qs.last_logical_writes, qs.total_worker_time, qs.last_worker_time, qs.total_elapsed_time/1000000 total_elapsed_time_in_S, qs.last_elapsed_time/1000000 last_elapsed_time_in_S, qs.last_execution_time, qp.query_plan FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) qt CROSS APPLY sys.dm_exec_query_plan(qs.plan_handle) qp ORDER BY qs.total_logical_reads DESC — logical reads […]

Creating a local Certificate Authority using OpenSSL

Unknownbolt | 2017-10-30

I was recently tasked with creating a local CA for a project, where we needed to verify custom client certificates, have the ability to revoke them at will, and we wanted to add additional custom fields to the certificates. Cool. The first stop after searching a bit was this excellent howto by Jamie Nguyen. There’s […]

Shrinking a Raspbian installation and re-enabling auto expanding for distribution of customized images

Unknownbolt | 2017-10-18

UPDATE: See the automated script at https://blog.dhampir.no/content/script-for-creating-a-compressed-image-file-from-a-raspbian-sd-card Raspbian, by default, expands to fill the SD card it finds itself on, the first time it boots. After having customized an image to your liking it would be favourable to avoid copying 16 gigabytes of data, or however large your chosen SD card is, each time you […]

Handling multiple overlapping VPN client networks with pfSense and a reflector VM

Unknownbolt | 2017-10-16

Following up on my recent post about making a minimal VPN routing virtual machine to isolate obnoxious VPN clients, another problem you’ll run into if you have the need to connect to a whole lot of client networks is that the networks of different companies tend to overlap, either with your own or with eachother. […]

Making a minimal VPN routing virtual machine to isolate obnoxious VPN clients

Unknownbolt | 2017-10-15

After it was requested multiple times on my post about using pfSense as a Cisco AnyConnect VPN Client, I finally found some time to document the setup I ended up with as a replacement, the purpose of which was to not clutter up the pfSense box. pfSense, after all, acts as the main company router […]

BashDB, a single dynamic database table for bash scripts

Unknownbolt | 2017-10-09

I write shell scripts. A lot of them. I automate everything with scripts. Many of these scripts need to have some notion of a state. The state needs to be persistent. How do we do that? And could we draw some retro flashback line character table borders while we’re at it? The problem If I […]

Upgrading the Vostro 1700 to beyond maximum specs

Unknownbolt | 2017-09-24

WARNING: This post is very specific to an old laptop, probably only interesting to anyone looking to upgrade such a machine. I warned you. I have an unhealthy obsession with “maxing out” machines, especially older ones. It was time for the chunky old Vostro 1700 that now runs Windows 7 instead of the version of […]

How to set the default location for new computers in Active Directory

Unknownbolt | 2017-09-17

Just a short note to self here, as the process is fully documented at Microsoft’s website (local archive here). The command to use is: C:\windows\system32> redircmp ou=mycomputers,DC=contoso,dc=com Of course you have to customize the location to fit your domain.

Figuring out which session is blocking a query on Microsoft SQL Server (query suspended)

Unknownbolt | 2017-08-28

I was recently debugging a case where a customer’s installation was hanging due to a database lock. The issue turned out to be that the database was not set to a default transaction level of READ COMMITTED SNAPSHOT, which the product expects. Regardless, while troubleshooting the issue, I stumbled upon a very useful SQL query […]

Using IPv6 SLAAC with IP forwarding on Debian Stretch (“connect: network is unreachable”, no default gateway)

Unknownbolt | 2017-07-27

When configured as a router, for instance for hosting virtual machines with KVM, a Debian machine with a somewhat recent kernel will not listen to router advertisements from others. This makes sense in many cases, but when you have a VM host in your internal network, which only router function is to allow communication to […]