Wed 06 February 2019
Sat 02 February 2019
Everything is a semi-rational reaction to something else.
Companies used to own and run their own machines on-premises. But doing it properly (HVAC, power, raised floors, standardized racks, management, redundancy, preparedness…) is expensive and not actually most companies’ core competency. So they moved to colocated datacenters, where a competent company would take care of the infrastructure for a fee which would hopefully reflect a discount based on savings from scale.
But managing generations of servers at colo datacenters takes manpower for hardware replacement, upgrades, cabling, and generally doing things right; the customer companies mostly don’t have that as a …
Tue 22 January 2019
It’s 2019. How much RAM do you need?
For a desktop or laptop, it’s fairly easy: everyone needs 8GB to get general work done. 16GB is suitable for people who are doing heftier work, and people who need 32GB or more always have a specific reason that they can articulate and justify.
Servers are different. Servers can be scaled vertically (made or purchased in heftier configurations) for a ways, but nearly always you will have a reason to scale horizontally (more machines of the same calibre) – high availability, or recovery from disaster, or workloads that are cost-effective to …
Sat 15 December 2018
The HP Envy 13z is a lightweight, reasonably high-performance laptop with a relatively low price tag - under $600 for the 1080P 13” touchscreen, flip-hinge to tablet, backlit keyboard, 8GB RAM, 250GB SSD, Ryzen 2300U four-core system weighing a little over two pounds.
(Those were the specs.)
It generally compares favorably to a non-Retina MacBook Pro.
Unsurprisingly, it ships with Windows 10 and HP support wants nothing to do with Linux. Honestly, if they just changed their stock answer away from hostility to polite indifference, it would be a remarkable improvement. Running Windows disk management utility produced a 112GB partition for …
Wed 12 December 2018
We’ve had a nominal gigabit fiber connection for more than a year now. Let’s take a look at how much of it we’ve been using.
Luckily, my firewall keeps track for me.
$ vnstat -m -i eth3
|month | rx | tx | total | avg. rate|
|Jan ‘18||476.82 GiB||26.09 GiB||502.91 GiB||1.58 Mbit/s|
|Feb ‘18||430.73 GiB||30.39 GiB||461.12 GiB||1.60 Mbit/s|
|Mar ‘18||382.38 GiB||17.60 GiB||399.99 GiB||1.25 Mbit/s|
|Apr ‘18||452.32 GiB||17.65 GiB||469.97 …|
Sat 17 November 2018
There’s this notion of a technological cycle of reincarnation, where an implementation is followed by a logical successor which leads to another one which carries on down a chain until someone has a bright idea which looks an awful lot like the original implementation. For example, it used to be that CPUs did all their math by themselves, then they outsourced the hard parts to floating point coprocessors, then those got built in to the main CPU chip again. Graphics subsystems are particularly prone to the cycle.
It just occurred to me that with the recent trend to enabling …
Mon 05 November 2018
I remember that there are test patterns built into T1 CSU/DSUs, but not what they are or how to turn them on – if I need to know, I’ll look it up.
I remember that there are three QoS bits in the IPv4 header, but not where they are. Probably pretty early, because of hardware implementations.
I remember that lots of people look down on Perl 5’s object system, but not why. I remember the existence and purpose of lots of Perl modules, but not the interfaces.
I edit JSON and YAML every few weeks, but I don …
Fri 02 November 2018
Recognize this pattern:
- Set a goal
- Work towards the goal
- Evaluate progress:
- If it didn’t get closer to the goal, try a different approach.
- If it got closer to the goal, try improving it.
That seems reasonable, right? It accomplishes what you wanted to do, possibly in a naive manner.
Okay, let’s look at the serious problems:
Mon 22 October 2018
Several people have asked me recently what hardware I would buy today for use as a home firewall.
- Partaker N3050 B5
- N3050 CPU
- no RAM (1 slot DDR3L up to 8GB)
- no SSD (room for mSATA + 2.5” SATA disk)
- 2 x gigE + wifi 802.11 b/g/n
- 2GB DDR3L RAM
- 2GB RAM
- Kingston 120GB mSATA SSD
- 120GB mSATA SSD
for a total of $176, including shipping. Links were accurate as of October 22, 2018.
This gets you a tiny box, similar in size to random commercial house router/firewall/wifi access points, which can run a standard Linux operating system with a complex firewall running at 1 Gb/s in and out, more RAM than strictly necessary, and an SSD which is both very large (and therefore can last a very long time) and boot the system quickly enough that you can do a reboot without losing TCP sessions.
I would also recommend a medium-sized USB thumb drive to set up as an emergency booting and backup device. Call it another $15 or so.
Sat 20 October 2018
About a year ago, we switched ISPs from RCN to Verizon. I had no particular issues with RCN except that their prices went up each year without providing better service. (It’s true that RCN also fails to handle IPv6 natively, but Verizon shares that failure.) What’s happened in that year?
Three outages. Two were caused by trucks knocking down the fiber crossing the road; one by an unspecified problem that was fixed by rebooting the Optical Network Terminal (i.e. fiber termination device, which offers ethernet, cable TV and telephone services). The first fiber outage took a week …
Thu 18 October 2018
In the distant past, the functions of author, editor and page designer were separated. The author wrote things; the editor fixed errors (both objectively and subjectively) and selected choice bits to highlight; the page designer made things look the way they should. The editorial intermediary didn’t consult the author much, and gave limited direction to the page designer.
Pull quotes appeared where the page designer put them.
Because the editor could not predict where the pull quote would be located on the page, it made sense that the quote would not actually be removed from the text body, but …
Wed 10 October 2018
All email disclaimers are utterly useless – except, possibly, one that a lawyer sends you that, on that particular message, reminds you that you are not in a privileged relationship.
Here’s the proof:
This message (including any attachment(s) hereto) is confidential and may also be privileged. It is intended solely for the addressee. If you are not the intended recipient you are hereby notified that any disclosure, copying, distribution or taking any action in reliance on the contents of this information is strictly prohibited and may be unlawful. If you have received this message in error you are requested …
Fri 21 September 2018
One problem: we have built an immense network of supercomputers that is essentially a Commons. An abuse of this Commons that would be ridiculously unprofitable if it had to be carried out by humans – say, an expected return of one one-hundredth cent per attempt – is highly attractive to unscrupulous actors who can automate a billion attempts for an expenditure of a few days or weeks worth of setup and expect a hundred thousand dollars of return.
Another problem: there has been little incentive for software developers to guarantee the security (integrity, privacy, trustworthiness) of their products, because they face so …
Tue 28 August 2018
I work at a small technology company, recently moved from Cambridge to Boston. The new landlords were a little surprised that we wanted to expand the kitchen. This is what we normally supply to our employees and guests:
We have an espresso machine (and will teach you how to use it), a drip machine, a French press, a coffee grinder, a rotating selection of coffees including decaf in the freezer, about twenty kinds of tea/herbal tea/tisanes…
and a refrigerator stocked with skim milk, whole milk, half-and-half, heavy cream (usually), lemon juice, lime juice, soy and/or almond milk …
Sun 19 August 2018
“Move fast and break stuff” is a decent philosophy if and only if the consequences of breaking stuff are survivable.
If breaking stuff means that your website looks weird, that’s survivable.
If breaking stuff means that performance sucks for a while, that’s survivable.
If breaking stuff causes unavailability during a critical period of end-user demand, a few incidents might be survivable.
If breaking stuff causes your company to have a terrible reputation for privacy, security, or competency, that might not be survivable.
If breaking stuff causes your company to divulge financial information, that might not be survivable.