1984 – the techblog

(Hopefully) useful various sysadmin and other stuff.

ReVox A 78 MK II: Adjusting Input Balance

I did recently mount my main loud­speak­ers to the walls. How­ever, after some lis­ten­ing tests I got the feel­ing that some­thing was amiss; for some rea­son, i felt that the stereo cen­ter wasn’t really cen­tered. The bal­ance turn­ing knob was set cor­rectly though, so that couldn’t be the issue. Thank­fully, the A 78 has gain controls […]

Social Network Integration

Yup, in order to make it eas­ier for users to com­ment and link, I enabled FB login’s here (even though I hate those Login– and Like-Buttons every­where) for the time being. This isn’t defin­i­tive how­ever. After all, there will be some­thing else after Face­book (and No, g+ is acti­vated for some­thing com­pletely else in case you […]

md write-intent bitmap

Few know about a fea­ture that has been intro­duced to md since a few years now: The write-intent bitmap. This might be mainly because it’s not enabled by default (more about why later) and isn’t really vis­i­ble in day-to-day oper­a­tions. So what is it exactly? Taken from md(4): If con­fig­ured, the bitmap is used to record […]

TFTS 2: How to get stable RAM

In TFTS 1, I talked about my expe­ri­ence with bad RAM that kept screw­ing up my chi (Note to self: return those soon). But as with the cur­rent state of con­sumer grade RAM, how to get some­thing rock sta­ble for home use ? Aside from the cost, most often you can’t even use server grade RAM […]

BSD watch (or: poor man’s GNU watch)

On GNU, there’s a neat com­mand to keep an eye on arbi­trary com­mands. It’s very use­ful when a fel­low sysad­min needs to mon­i­tor some­thing else than log files, or trace bina­ries. Naïve as I am, I tried to use this on a FreeBSD sys­tem as well, only to dis­cover that the default watch com­mand does […]

Bash: Handling various versions of wc

I really love the wc tool. For those who don’t know it, it sim­ply counts words, lines, char­ac­ters and bytes of any input it receives on STDIN. You’d be sur­prised how often one needs this func­tion­al­ity! But, as with many things POSIX/UNIX, there are dif­fer­ent flavours avail­able; while many tools have the same name on all […]

Get the sum of a column in shell (using awk) or: find out cumulative memory consumption

The title already gives it already away, awk is the tool to use here: awk ‘{ SUM += $YOUR_FIELDNUMBER} END { print SUM }’ where YOUR_FIELDNUMBER is the num­ber of the col­umn you want to sum (the dol­lar sign is required!). I needed lit­tle one­liner to find out how much mem­ory php was con­sum­ing on a […]

Compiling transmission fun (FreeBSD)

Com­pil­ing trans­mis­sion can be a bit funny (read: not fun) some­times. I faced this task on a locked down FreeBSD sys­tem. Here’s what errors I encoun­tered, and how I was able to solve them. Don’t for­get to do a make clean after you’ve mod­i­fied a file (per­haps even re-run con­fig­ure). make: don’t know how to make ./libtransmission.a. […]

Hidden Gems: Boolean Spotlight Queries

By now, any decent user of Mac OS X will know and have used Spot­light. Maybe loved, maybe hated it (I’m slowly com­ing to terms with it). In clas­sic Apple fash­ion, it’s dead sim­ple to use and needs only a text input field, where you enter what­ever comes to mind when you’re look­ing for that […]

TFTS 1: What NOT to do when your server crashes randomly.

I recently built a lit­tle server whose main task is to serve files. Bought a moth­er­board that had a decent amount of SATA ports, added two addi­tional SATA con­troller cards and packed the whole case full of disks. As the server is at home, I didn’t bother with enterprise-grade hard­ware stuff. Fun was had, but soon […]

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