Add old posts from Journal

Some of the entries in my journal are particularly detailed and/or
informative, so I thought they would make good blog posts.

content/posts/ansible-sudo-bw.md

@@ -0,0 +1,11 @@
+---
+title: Ansible, sudo, Bitwarden
+date: 2019-08-20T06:54:00-06:00
+---
+
+The latest version of `sshpass` supports a `--prompt`/`-P` argument, which
+controls the string the tool expects, after which it will send the specified
+password.  Using this, it is possible to send a password from Bitwarden to
+Ansible, like so:
+
+  sshpass -f <(bwpass …) -P 'SUDO password:' ansible-playbook -bK …

content/posts/fedora-update-roroot.md

@@ -0,0 +1,12 @@
+---
+title: Updating Fedora with Read-Only Root Filesystem
+date: 2019-11-12T15:52:00-0600
+---
+
+When using `dnf system-update` on a Fedora machine that has a read-only root
+filesystem, it is important to make sure that the filesystem will be mounted
+read-write automatically first.  Edit `/etc/fstab` and change it to `rw`
+before rebooting, lest the update will fail.
+
+I imagine the offline update process really should remount the root filesystem
+on its own, but that does not appear the case, at least for now.

content/posts/grafana-sensor-data.md

@@ -0,0 +1,18 @@
+---
+title: Graphing Sensor Data with Grafana
+date: 2018-08-06T21:32:00-06:00
+#draft: true
+---
+
+To view trending sensor data, I installed collectd (with the "sensors" plugin
+enabled), InfluxDB, and Grafana. For some series, Grafana displayed wierd
+graphs with what looked like two values for one interval. I worked around this
+by changing the Influx query from
+
+    SELECT "value" FROM "sensors_value" WHERE ("type" = 'temperature') AND $timeFilter GROUP BY "type_instance"
+
+to
+
+    SELECT median("value") FROM "sensors_value" WHERE ("type" = 'temperature') AND $timeFilter GROUP BY time(10s), "type_instance"
+
+This seemed to smooth out the line quite a bit.

content/posts/improving-influxdb-queries.md

@@ -0,0 +1,15 @@
+---
+title: Improving InfluxDB Sensor Data Queries
+date: 2018-08-07T18:28:00-06:00
+---
+
+I now understand why Grafana built the initial query with `GROUP BY
+time($__interval)`. With a hard-coded value in `time()`, every single point is
+displayed on the graph, regardless of the zoom level. The `$__interval`
+variable scales this value based on the time period displayed.
+
+Initially, this did not work for me, and Grafana just drew seemingly random
+points when using any view besides "last 6 hours." This turned out to be
+because the default value for "min time interval" was not set (or was
+incorrect). Seting it to "10s" (which is the collectd poll interval) corrected
+this issue as well.

content/posts/new-tool-mizule.md

@@ -0,0 +1,41 @@
+---
+title: >-
+  New Tool: Mizule
+date: 2020-01-17T23:01:00-05:00
+---
+
+I want to do better about switching out the BURP backup disks, so I need
+something to remind me.  A calendar event might work, but if I forget to do it
+on the day it's scheduled, I won't get another reminder until the next
+scheduled date.
+
+I decided to write a simple program that checks the UUID of the filesystem
+mounted at /var/spool/burp and generates a notification if it has not changed
+for some time.  This way, if I forget to do it on the scheduled date, it will
+keep reminding me until I do.
+
+I wrote the tool in Rust, because it is very simple and I have been looking
+for a project to help me get motivated to learn Rust more.  It took about 12
+hours start-to-finish.
+
+Aside from my lack of familiarity with Rust, probably the most difficult part
+of the project was getting it to reliably send email notifications!  At some
+point, I realized that `nullmailer` wasn't running on my desktop, and hadn't
+been for *quite* some time!  When I started it up, it had so many messages
+queued up (from cron, etc.), that Protonmail put a rate limit on my email
+account!  This made it difficult to test Mizule's email capability, since I
+couldn't actually see the messages it was sending, only that it had sent
+something according to the Postfix logs.
+
+I am going to look into some other options for sending push notifications.  So
+far, I have found [Firebase Cloud Messaging][0], Google's "offical" push
+notification solution, which naturally requires a Google account, Google
+Services Framework, et. al.  I also found [Gotify][1], which just uses a
+WebSocket.  There is also [notify.run][2], which uses the Web Push API (browser
+based), and [signald][3], which sends messages to Signal.  XMPP may be an option
+as well.
+
+[0]: https://firebase.google.com/docs/cloud-messaging/
+[1]: https://gotify.net/
+[2]: https://notify.run/
+[3]: https://gitlab.com/thefinn93/signald

content/posts/xrdp-experiment.md

@@ -0,0 +1,25 @@
+---
+title: Experimenting with xrdp
+date: 2019-08-08T10:38:00-06:00
+---
+
+I needed to use the iDRAC on the prototype appliances to install FMOS. I tried
+several ways of using the Remote File Share feature to map the virtual media
+(HTTP, NFS, CIFS), but could not get any of them to work: most options
+appeared to do nothing, giving an error message about invalid path or
+credentials, without even attempting to connect to the specified server. I
+knew that the client-side virtual media would not work over the VPN, so I
+decided to try setting up a GUI on a machine in the office to run Firefox and
+the iDRAC virtual console applet, and then connect to it remotely.
+
+On Fedora, setting up xrdp was pretty simple. I just installed the *xrdp*
+package, which pulled in the *xorgxrdp* and *xorg-x11-server-Xorg*. Besides
+adding the port to the firewall, the change I had to make was to create
+`/etc/X11/Xwraper.config` and set `allowed_users=anybody`, to allow non-local
+users to create X sessions.  Then, just starting the *xrdp* service was all
+that was necessary.  I did have to work around a bug by passing `+glyph-cache`
+(or ticking the corresponding checkbox to `xfreerdp` to get the client to
+connect, but otherwise, the process was pretty smooth.  I then instaled
+*firefox*, *i3*, and *icedtea-web*.  The only part that was somewhat confusing
+is that `~/.xinitrc` did not work; the launch script had to be named
+`~/startwm.sh`.