Sunday, August 23, 2015

Stateless DEIS - no Ceph

I'm sure Ceph is fine.  But, I don't want to add any uneccesary complexity to my DEIS cluster.  And, I don't know Ceph well enough to feel comfortable keeping it if I don't have to.

Below are a few notes I took in trying to get my stateless DEIS 1.9.0 cluster going.

First, I needed a log server to which I could send syslog from DEIS.  BTW, the "deis logs" command will cease to work once you send them to an external syslog service.  We are testing CloudWatch Logs.  Funny enough, I ended up trying Amazon ECS to host a docker image configured with CloudWatch Logs.  I fired up a service with two syslog tasks (listeners).  I will use these syslog servers for other purposes as well.

Second, I needed a PostgreSQL database.  RDS to the rescue.  So far, I'm getting by with a t2.micro.

Third, I needed some external storage for real files.  DEIS allows for an S3 backend.  I found no documentation for required permissions.  So, I tinkered until I came up with this small set:

    "Version": "2012-10-17",
    "Statement": [
            "Sid": "Stmt1440163063000",
            "Effect": "Allow",
            "Action": [
            "Resource": [
            "Resource": "arn:aws:s3:::the-bucket",
            "Action": "s3:*",
            "Effect": "Allow"
            "Resource": "*",
            "Action": "s3:ListAllMyBuckets",
            "Effect": "Allow"

The special deis install stateless-platform & deis start stateless-platform are the commands used to turn up the lean environment.  I had trouble with the registry starting until I tweaked the S3 permissions.  The builder wouldn't start because the controller didn't start (/deis/controller/* etcd keys didn't exist).

After much angst, and by running each command in fleetctl cat deis-controller individually, I found that the password for my postgres database had a single quote in it.  My luck, the startup script also used single quotes around the password.  FAILHORN!  After getting the controller whipped into shape, it still shows as inactive/dead in deisctl list.  But, I can register/login; and, the builder automatically continued after the controller came on.

So, I just first my first app to it.  I'm already enjoying (of necessity) those CloudWatch Logs.  Weeee!

Saturday, August 22, 2015

Arduino On Ubuntu 15.04

The Arduino Uno clone I picked up from a Chinese Ebay seller has a USB-to-serial adapter that lacks Mac support.  Well, there is a Mac driver.  But, I wasn't comfortable installing a driver whose download link (and installer, I think) was only in Chinese.

Luckily Linux has the driver built right in.  So, using my Ubuntu 15.04 laptop, I installed Arduino 1.0.5 from the default apt repositories.  First thing I found was that the "Tools->Serial Port" menu item was grayed out.  I added myself to the dialout group and logged out/into my X session (or run newgrp and then run arduino from the terminal).  I found that I could not save or open a file.  I was using Iced Tea java.  I pointed at java 7.x.  No luck.  Turns out, it depends on Java 6 runtime, still available in Oracle's archive area.

My son and I played with the blink example.  I'm so glad that little LED is built in!

Back to coding.  So long.