Perilous Codpiece Blæg

I’m always a bit nervous kicking off remote server OS upgrades, but shoutout to the Debian team for making this another smooth one from 11/bullseye to 12/bookworm. The only quasi-glitch I encountered was that the apache php module wasn’t installed automatically during the upgrade, but that took all of 30 seconds to fix.

Since TP-Link’s documentation is *awesome* for this (sarcasm alert), I thought I’d share what I finally figured out to get the self-signed cert replaced with one from a local CA that doesn’t make Chrome complain. This was the result of several hours of fiddling around, waiting for oc200 reboots, and getting uber-helpful error messages from the device (sarcasm meter explodes).

Pre-reqs:
1. passing familiarity with openssl command-line usage, including how to set up a local certificate authority (CA; out of scope for this post/rant but this looks decent as an intro: https://gist.github.com/Soarez/9688998)
2. the patience not to see how far you can shot-put the oc200 device
3. some machine with openssl installed (I used a linux machine running ubuntu 20.04 fwiw)

First, you’ll want to create a config file to save typing later and enable Subject Alternate Names for your cert (so the same cert’ll be valid from the controller raw ip, or name, or short name). Call it san.conf or similar.

[req]
req_extensions = req_ext
distinguished_name = req_distinguished_name
prompt=no

[req_distinguished_name]
countryName                     = 
stateOrProvinceName             = 
localityName                    = 
organizationalUnitName          = 
commonName                      = 
emailAddress                    = 

[req_ext]
subjectAltName = @alt_names

[alt_names] 
IP.1=192.168.5.2
DNS.1=oc200.lan.example.com
DNS.2=oc200

Now, on to making the actual cert (filenames may of course be altered to your taste, just be consistent):

1. openssl req -new -keyout oc200.key -sha256 -config san.conf -out oc200.csr
a. note that you probably want a password here (used by key).
b. if you’re ok with a less secure key sans password, add a -nodes argument above

2. openssl x509 -req -days 365 -in oc200.csr -CA -CAkey -CAcreateserial -extensions req_ext -extfile san.conf -out oc200.crt
a. note that recent chrome builds are moving to deny validity of certs with longer than one year. (imho this is overkill for rfc1918 networks, but c’est la guerre.)

3. openssl pkcs12 -export -in oc200.crt -inkey oc200.key -out oc200.pfx -CApath /etc/ssl/certs/ -CAfile -caname root -name oc200 -chain
a. note that you probably want to use a password here as well
b. note also that the Omada web ui is picky about filename extensions. you’ll want to end your pkcs12-exported cert to end in “.pfx” to keep it happy on upload later

From here, with the pfx file and (optionally, but recommended) the key and pfx passwords, you can proceed to Settings > Controller > HTTP Certificate session, upload your pfx file, fill in any required passwords (be sure to pay attention to which password is which re: key vs cert file aka keystore), and save at the bottom of the screen. You will then want to go to Settings > Maintenance > Hardware Controller section and reboot (this will take several minutes to complete).

You may also need to do a full flush of your browser’s cache if there were earlier attempts with the same identity cert (e.g. accidentally making it valid for too long and learning a painful lesson). You will need to import the root CA cert into your browser/OS trusted roots collection as well if you haven’t already done so (out of scope for this, but googling something like “import root ca cert ” would help).

Hope this saves someone a few hours of irritation. :)

After five years at Oracle, I got thoroughly fed up with BigCo bullshit and have switched to an early-stage startup at a friend’s recommendation. This will be the fourth company I’ve worked with him at over the last ~20 years. It is *so nice* to get back into days that are filled with code instead of meetings, and with a tech stack I like to boot (java, linux, postgres, AWS) as well as some tasty new things to explore. (I typo’d that as explode at first and let’s be real, that’d work too for technology.)

oldstable to stable, not much to see here, move along :)

pc.o is now on debian buster after being on stretch for a while. no underlying hardware changes this time around.

Updating from oldstable to stable (what finally provoked me to get this done was oldstable reaching EOL status, heh). No major changes since last “pc.o update” post on the software side. I did end up dropping down to a $5/mo plan vs $20, just because honestly it’s all the resources this really needs (one core, 1gb, ~20gb/disk). As always, I know not many other than me use this server, but if you notice anything odd, feel free to reach out.

(Minor update: turns out I had a free upgrade to 25gb of disk from 20gb pending in linode; applied that. Whee!)

An ocean of ink has been spilled about interviewing for jobs in the technical industry (see, just for example cracking the coding interview or get that job at google). I’m probably not going to cover any new ground here, but these are some basic tips for doing better on technical interviews.

This post was inspired by my repeated recent frustration as a hiring manager watching candidates that had potential (or even proven prior performance!) do poorly at the in-depth interview loop phase of the process. If every candidate took fifteen minutes to read and internalize these points in addition to however many hours they spend self-flagellating with Cormen et al’s algorithms tome, I am guessing the pass rate might double. Interviewing is not like regular work (for better or for worse), and competency at the latter does not a priori translate well to the unnatural constraints of you + interrogator + whiteboard.

• When you’re practicing for an interview that will involve whiteboard time, write out your solutions long-hand on paper first, and make a note of what you have to google to remember. Not that an interview will be passed or failed based on remembering all the printf format specifiers or whatever, but it doesn’t hurt to get them right either.
• Ask questions before you dive in! (I would stipulate “good questions” but really, anything more than silence that’s on topic would be better than nothing.) Many many many times a problem can be dramatically simplified by asking clarifying questions or stipulating a reasonable constraint. No interviewer will hold this against you; on the contrary, it’s usually regarded as a small but very positive signal for the candidate’s competency.
• Think out loud as much as you can. Remember that we’re not just looking for banged out code or whatever, but trying to see how you think. Thinking is 90% of technical work, the rest is just typing and irritating planning meetings. If nothing else, outline the solution that comes to mind at a high level and ask if that sounds reasonable before diving into implementing it. That alone can save you many precious minutes from being wasted by barking up the wrong tree.
• Post-solution follow up work: after you’ve banged out an implementation, take a moment to talk — even at a footnote level — about efficiency / avenues for possible improvement / how to test your work. For example, in a code interview, take a moment to walk through a very simple test case. These are hugely positive signals that the candidate is driven to do good, thorough work and possesses initiative/responsibility/etc.
• Take a deep breath and relax. :) I know (I know) this is maybe the hardest element of this list, because you’ve got all this stuff riding on whether or not you pass the interview, and rightly you’re a bit stressed out with all of it. But your brain will work better if you aren’t in fight-or-flight mode. Try to, as much as is possible, relax and view interview sessions as a friendly chat to solve a problem between colleagues rather than an Inquisition. Good interviewers will make allowances for nerves, but still, it goes a lot easier if you chill out a bit about things.

Good luck!

Now that oldstable is oldoldstable, I bit the bullet and upgraded to jessie from wheezy. The upgrade process was surprisingly smooth. Systemd… well, many megabytes of flames have been written about that before. There isn’t much I can add to it other than a) the idea still disturbs me on some level b) pragmatically, it seems to work ok so far c) I have so many other things to worry about.

Since Debian just dropped a new stable version, I’ll probably upgrade to that in a while (~ a quarter or so, or whenever the first patch release drops) to give fresh bugs time to shake out.

No system capacity changes with this update. When pc.o first migrated to linode, I don’t remember for sure, but I think it was something like 512mb ram and (10? 20?) gb of disk. Now for the same price it’s 4gb of ram and 48gb of disk. The former felt a bit cramped at times, but now … I almost feel embarrassed to have so much capacity for what is fundamentally a personal fuck-around-with-shit server. I’d move to a smaller plan but it seems like a pretty big hassle potentially for a savings of maybe $10/mo.

I’m sure this is interesting to all like four or five of you who use pc.o for anything, but I felt obligated to keep the tradition of saying something about system updates alive. As always if you do use pc.o and notice something weird, let me know and I’ll try to fix it.

@patio11 is worth following on twitter, but in particular recently he posted this tweetstorm talking about the hiring and onboarding process that really struck me as being worth a read:

If there is a talent shortage, it is of people who know how to run a hiring process like it is a business.

— Patrick McKenzie (@patio11) August 31, 2016

I know you like *your* company's hiring process, but your peers'… if your sales team executed like that, you'd fire them in two weeks.

— Patrick McKenzie (@patio11) August 31, 2016

"How many leads did you talk to today?" "I dunno." "Guess for me." "Three? Could have been four."

— Patrick McKenzie (@patio11) August 31, 2016

"What's the status of this lead?" "Oh I DQed them." "Why?" "Culture fit." "What does that mean?" "Fit. For our culture."

— Patrick McKenzie (@patio11) August 31, 2016

"When's the last time you talked to Bob?" "Yesterday." "Show me the email." *shows email from 3 weeks ago promising a callback*

— Patrick McKenzie (@patio11) August 31, 2016

"Where's sell sheet vs Google?" "Our what?" "When they're considering us and Google, what tested message do we repeat?" "I wing it, dawg."

— Patrick McKenzie (@patio11) August 31, 2016

"Suppose an engineer intros you to a warm prospect. What's next action?" "Thank them." "And then?" "I'm thinking call w/ no script or CTA."

— Patrick McKenzie (@patio11) August 31, 2016

"What's our conversion rate?" "What's that word mean?" "How many leads did we get this quarter?" "Ooh, quarter means three months."

— Patrick McKenzie (@patio11) August 31, 2016

"Describe to me how we developed our sales process." "We copied a ten year old blog post repeating Google's third-hand." "Why?" "Google's!"

— Patrick McKenzie (@patio11) August 31, 2016

"Tell me how we do lead nurturing here." "What's that?" "Even if they're not ready to take a job we send them something, right?" "Lol why."

— Patrick McKenzie (@patio11) August 31, 2016

"You still working Amy?" "Yep." "Who can know that she trusts who we can ask to talk us up to Amy?" "That's both useless and impossible."

— Patrick McKenzie (@patio11) August 31, 2016

"How's our pricing compare to competitors?" "Better than market." "I know we tell people that but is. It. True." "Why does it matter?"

— Patrick McKenzie (@patio11) August 31, 2016

"So how did that sales call go?" "I asked an engineer to take it." "… You have a plan." "He flaked. Prospect was alone for an hour." /2

— Patrick McKenzie (@patio11) August 31, 2016

"JESUS CHRIST." "What?" "How do we salvage that prospect?" "He got pissy. Poor culture fit. DQed." "How do we never do this again?" "Why?"

— Patrick McKenzie (@patio11) August 31, 2016

"How'd last call go?" "Crap lead man." "OK, so how would you rate your performance on selling?" "Oh I only do that when excited about lead."

— Patrick McKenzie (@patio11) August 31, 2016

"What's customers purchasing process look like?" "Is that a trick? They use our sales process." "… OK. What's that look like?" "Wing it!"

— Patrick McKenzie (@patio11) August 31, 2016

"Who's the leads economic buyer?" "The lead. Duh." "They make all decisions." "Of course." "They ever ask anyone for input?" "Prob no. Why?"

— Patrick McKenzie (@patio11) August 31, 2016

"What were the deals you were happiest about last year at time of close?" "X, Y, Z." "Which is best one year later?" "What do you mean?"

— Patrick McKenzie (@patio11) August 31, 2016

"Explain to me how you qualify." "I've got hard DQs and soft DQs." "Name a hard DQ." "None exist." "A soft DQ." "Lead's school is subpar."

— Patrick McKenzie (@patio11) August 31, 2016

"What's the difference between a soft DQ and a hard DQ?" "Oh, a DQ is a DQ, unless I've got a vibe." "A vibe." "You know, like passion."

— Patrick McKenzie (@patio11) August 31, 2016

"Where do we source?" "Industry standard is to buy leads from 1 provider and scrape 1 free one." "And where do WE source?" "Like I said."

— Patrick McKenzie (@patio11) August 31, 2016

"What's your job here?" "Protecting the company from bad sales." "… Explain." "One bad deal closed worse than 100 good ones missed."

— Patrick McKenzie (@patio11) August 31, 2016

"Man we lucked out on X." "Yeah." "Where'd they hear about us." "Dunno." "Freebie: it was that blog post from Bob in DevOps." "Cool." /2

— Patrick McKenzie (@patio11) August 31, 2016

"So what are you going to ask Bob in DevOps to do for us?" "I don't follow." "How can we use Bob to accomplish our goals?" "Not on our team"

— Patrick McKenzie (@patio11) August 31, 2016

"I've got good news for you: Bob is writing another post." "Cool." "What are you going to ask Bob to say in that post?" "Uh I don't DevOps."

— Patrick McKenzie (@patio11) August 31, 2016

"Why'd you DQ this lead?" "Spelling mistake in an email to me." "… Explain." "Well that says 'careless.' They know how important I am."

— Patrick McKenzie (@patio11) August 31, 2016

"Why'd you DQ this lead?" "Spelling mistake in an email to me." "… Explain." "Well that says 'careless.' They know how important I am."

— Patrick McKenzie (@patio11) August 31, 2016

"What do we have that Competitor X doesn't have?" "Culture." "Imagine you worked for X and question reversed. Answer?" "Hmm, culture."

— Patrick McKenzie (@patio11) August 31, 2016

"What's an ask you could make of any team in company that would make your sales job easier?" "Dunno." "Make one up." "We could use Ruby?" /2

— Patrick McKenzie (@patio11) August 31, 2016

"GREAT. OK, who do we have to ask internally to start using Ruby?" "Dunno." "Probably VPEng. How would we ask him to?" "Not my job to."

— Patrick McKenzie (@patio11) August 31, 2016

"What happened to Susan?" "Went with a competitor." "Which one?" "She wouldn't tell me." "… So which one?" "What so we hire private eye?"

— Patrick McKenzie (@patio11) August 31, 2016

"Susan went with a competitor." "Sucks, yeah." "So when are you following up with Susan?" "Did you not hear 'went with a competitor' boss?"

— Patrick McKenzie (@patio11) August 31, 2016

"But… what if Susan isn't happy with the competitor?" "Good. She was disloyal. No culture fit." "Why'd she owe us loyalty?" "Well DUH."

— Patrick McKenzie (@patio11) August 31, 2016

"Who out-executes us at sales?" "Competitor X." "Why?" "They're Internet famous." "What does that mean?" "They have a blog." "Do we?" "No."

— Patrick McKenzie (@patio11) August 31, 2016

"So they're out-executing us, on something important, because they have a blog." "Yeah." "So when are you starting to blog?" "I'm busy."

— Patrick McKenzie (@patio11) August 31, 2016

"Why should people join us?" "The mission!" "Who articulates the mission best?" "The CEO." "Do we have her talk to candidates?" "Lol no."

— Patrick McKenzie (@patio11) August 31, 2016

"Why not?" "Because she's the CEO and has important work to do." "OK but we have video of her talking right." "Yeah." "Do we send it?" "Why"

— Patrick McKenzie (@patio11) August 31, 2016

"Explain 'equity' to someone who has never heard it before." *does* "Explain why we use NQSOs to 10 year veteran." *same explanation*

— Patrick McKenzie (@patio11) August 31, 2016

"So you're in the biz of convincing highly mathematical individuals to trade stock for money." "Yep." "How much is our stock worth?" "Lots."

— Patrick McKenzie (@patio11) August 31, 2016

"Your answer on valuation is 'lots.'" "Well 'not lots' clearly wouldn't get it done right?"

— Patrick McKenzie (@patio11) August 31, 2016

"Could we give devs well-designed Excel spreadsheets with valuation calculators." "A good idea." "Do so." "I don't design/Excel sorry."

— Patrick McKenzie (@patio11) August 31, 2016

"You don't do design or Excel." "No." "OK, let me take another tact: who in a software company does design or Excel?" "Lol nobody."

— Patrick McKenzie (@patio11) August 31, 2016

"What we spend on outsourced lead gen last quarter?" "$0." "What do we pay recruiters?" "$25k a placement." "How many placements?" "Ten."

— Patrick McKenzie (@patio11) August 31, 2016

"OK, so imagine you had a $250k budget for making stuff." "They'd never give me a budget." "Play along. What would you make?" "Sounds risky"

— Patrick McKenzie (@patio11) August 31, 2016

"OK, I get that. Imagine its your hated rival at Competitor X. What could *they* get made for $250k?" "Dunno." "How many books/movies/apps?"

— Patrick McKenzie (@patio11) August 31, 2016

"Dunno." "What's a book cost to make?" "Dunno." "I assert it can be done for $50k." "Sounds unlikely." "Can you turn book into candidates?"

— Patrick McKenzie (@patio11) August 31, 2016

"I can't imagine devs read books." "OK, do they use websites?" "Yeah." "Can you get a website made?" "We have a jobs page." "Think bigger."

— Patrick McKenzie (@patio11) August 31, 2016

"Bigger than a jobs page?" "Yeah." "Like, a jobs *listing* page?" "Like something that an engineer outside our company would enjoy using."

— Patrick McKenzie (@patio11) August 31, 2016

"I don't know, that sounds like a Project." "Ever asked any dev in this company what they did over a weekend?" "Apps or some shit I dunno."

— Patrick McKenzie (@patio11) August 31, 2016

"Could your hated rival, with $250k, possibly cause an app that devs would use to exist?" "Buy dev time? Lol. Impossible right."

— Patrick McKenzie (@patio11) August 31, 2016

As the CEO of a company dedicated to improving the technical hiring process, he is to some degree talking his own book here, but his points are incredibly valid. Hiring is fundamentally a sales process, and yet at most companies it is run by people who do not understand that (or, typically, anything about the roles they’re trying to fill, but that’s a rant for a different day).