Wait, what?? Those are a thing?

I’ve seen some rechargeable smoke detectors but never had a reason to trust those. Everything else has used the old school 9v.

Literally this.

Twice a year I fill in as DBA when our lady graybeard Oracle DBA takes vacation. This month is one of those times. Yay me.

For my org, it’s just the massive in-house developed line-of-business application that’s tightly coupled to Oracle that keeps us chained to it. It’s technical debt from top to bottom, and has been accumulating steadily since the early 2010s, but no one seems willing to start replacing it.

The new projects typically go with Postgres, MariaDB, or if all else fails, MSSQL. But the Oracle monster in the closet isn’t likely to leave any time soon.

If only 9 volts were that price, I’d stock up for the smoke detectors for the next 5 years.

For everything else, I bought a bunch of rechargeable AA and AAAs a while back and those have been great. Haven’t used a D battery in years and a C battery for decades. I assumed they stopped making C’s.

They can browse for free to see what it’s about. That’s how ArsTechnica works, and I’ve been a subscriber there for 10+ years.

Sometimes a little bit of friction and slight gatekeeping is a good thing. As my massive block list can attest, not everyone who signs up here makes the fediverse a better place.

Still get the benefit of the determined people funding the instances they’re using.

Oh, yeah. SSH from laptop or Termux on my phone.

Not sure if there’s a CLI way to deal with captive portals or not. Maybe a text-based browser like Lynx/Links2 if the portal isn’t super fancy, but I’ve used the MAC cloning method for ages and it’s just my “go to” for dealing with that. Honestly, I don’t deal with them very often since I just use a hotspot much of the time with it.

I’ve only had to go through a captive portal once with it but MAC cloning was sufficient

Security is pretty minimal, not gonna lie.

There’s a 50 GB LUKS partition that stays locked unless I’m actively using it. It’s got backup copies of my important/critical documents and password manager exports but the rest of it is just media and doesn’t really merit encryption.

All applications have local accounts but I’m not using LDAP or any kind of SSO like I am with my main stack.

At home, I keep the firewall disabled on the interface configured as “WAN” so I can access its services directly via their hostname (I point its wildcard DNS record to its local “WAN” IP) but do enable firewall when I’m using it on an untrusted network. Granted, I have to manually remember to do that, so that’s kind of a security risk if I forget. Generally, though, when I’m using it remotely, it’s using my secondary phone as a USB-tethered uplink so even if I leave its internal services exposed to WAN, the NAT from the phone blocks that. One of my goals, eventually, is to automate some of the firewall rules depending on where I’m using it.

Either the 3rd one or the least important one. Whichever causes me the most inconvenience.

Bonus “Mildly infuriating”:

Ask 4 bullet-point questions in an email, they only answer one of them and ignore the rest.

Definitely does, and it’s a beautiful city, but I never want to drive in it ever again lol.

Had to travel there 3 times for work. The first time I rented a car and immediately regretted it. The second and third times I demanded that management reimburse me for taxis instead of the car rental or I wouldn’t go lol.

Boston. IYKYK.

Yeah, please accept my downvote. If I wanted political “humor” I would unblock one of the many, many, many political meme communities this could have been posted in.

I hand wash them all with soap and water, but they all seem to lose their ability to shed off what I cook in them.

You need to oil them after washing them (wipe them down with a thin layer of vegetable oil or shortening).

Also, it may be time to reseason them if everything sticks even if you’re pre-heating it before adding the food. See: https://www.foodandwine.com/how-to-reseason-cast-iron-8600860

Yep. My house is block and brick and just soaks up heat all day and very slowly releases it at night. Unless there’s a 20-30 degree (F) difference, it just doesn’t cool down at all. It’s even worse when the night time temps don’t drop significantly until just an hour or two before dawn when it starts heating back up again.

That’s great in the winter since a sunny day can “store” heat for the night, but it’s miserable in the summer and you basically just have to pump it out with A/C.

Ah, yeah, you can have most devices with lithium batteries in your checked baggage, but they have to be off and packed so they’re protected from damage. It’s preferred for those to be carry-on items but isn’t required.

Power banks, vapes, spare batteries, etc are specifically prohibited in checked baggage and must be in your carry-on or on your person.

–https://www.faa.gov/newsroom/lithium-batteries-baggage

I think it’s the other way around, at least in the US. The last time I flew, anything with a lithium battery had to be either on your person or in your carry-on and couldn’t exceed a certain amperage/watt-hour rating. I remember having to check specifically on that since I wasn’t sure if I could bring my vape.

But mostly, a bare PCB with two 18650’s visible isn’t something I want to have to explain to airport security lol. They may let it pass, but it’s definitely going to be a hassle. Easiest to just use an approved power bank or just power it from my phone’s USB port. The UPS was mostly so I could make it mobile and use solar chargers with it.

It’s kind of a mix of things duct-taped together, but here’s the gist of what controls what. If you want to see any specific configs, let me know.

Network Manager controls the “static” interfaces. I’ve got some udev rules for my known hardware (USB wifi/ethernet adapters) so that they get friendly names as opposed to ugly “predictable” names.

The interfaces managed by NetworkManager are:

• STA mode Wi-Fi (internet uplink)
• LAN Bridge
• Wired Ethernet (internet uplink)

Connecting a USB-tethered smartphone is pretty plug and play. It automatically gets picked up as a USB ethernet interface, receives its IP address from DHCP, and gets set as the default gateway. So there’s nothing that needs to be configured when using that as the internet uplink other than making sure there’s no other active gateway that might interfere.

The LAN segment is a generic Linux bridge called br-lan (I’m borrowing OpenWRT’s naming convention). In normal operation, it has wlan1 and usb0 as members (AP and USB ethernet gadget, respectively). If I need a wired ethernet port on the LAN side, I just plug a USB ethernet adapter in and add it with brctl addif br-lan eth{XXX}

The usb0 ethernet gadget interface is brought up using a script that runs at boot via systemd to configure a libcomposite ethernet gadget before the network target. This ensures it’s available when the network comes up so it can be successfully added to the LAN bridge.

When changing out of the default configuration, I just go into network manager to enable/disable the correct interfaces. e.g. If I want to use wired ethernet for uplink and internal wifi for client AP, I enable the wired ethernet and disable the internal wifi’s connection to the router. Then I swap hostapd conf files to use the one configured for the internal wifi instead of the USB one and update the members in the LAN bridge accordingly. e.g. brctl delif br-lan wlan1 ; brctl addif br-lan wlan0

To add a LAN-side wired ethernet, I just make sure it’s not already configured for “WAN” in NetworkManager and add it to the LAN bridge. That, or setup a VLAN interface and use a single USB ethernet adapter for both (haven’t done that on this device but I know it works from having done that in the past).

Thankfully, PiHole exposes the DHCP controls for its underlying dnsmasq and since I’m already running PiHole for ad blocking and DNS, it was natural to also use it for DHCP. It’s configured to advertise addresses to the br-lan interface only.

Routing/NAT is all done directly with iptables. The VPNs dynamically update it as they connect/disconnect using their up and down hook scripts, and for the NAT used for client connections, it’s basically just iptables -t nat -A POSTROUTING -s $SOURCE_CIDR -o $OUT_INTERFACE -j MASQUERADE where SOURCE_CIDR=192.168.5.0/24 is the LAN segment address range and OUT_INTERFACE=wlan0 is the uplink interface (in the default configuration).

I’ve got some ugly scripts to adjust the NAT rules depending on which interface is currently acting as the “WAN” interface.

I addressed that in a few ways:

1. I bought a quality SD card to start with. A 1 TB card is a lot of eggs in one basket so I wasn’t about to cheap out on that part.
2. The board has 32 GB of eMMC which is where the OS is installed
3. There are very few writes to the SD card during normal operation (after initially loading content onto it). Running data (DBs, caches, log dirs, etc) for most applications is stored on the eMMC rather than the SD card or in some cases written to tmpfs (logs).
4. The subset of content I loaded onto this from my main media server was all chosen because it has the most re-watch potential, so re-loading close to a TB of media isn’t something that’s going to happen too often. The largest write it sees is the semi-annual refresh of the full ~130 GB Wikipedia ZIM dump, but I may push that back to once a year. I’ve only updated it twice so far.
5. Armbian assumes it’s going to run from SD card and does a pretty good job about minimizing the number of writes. Logs are all written to zram and only occasionally written to disk, it has no swap file, etc. If those are good enough to keep an SD card happy, they should keep an eMMC even happier.

Basically, I tried my best to configure the SD card so that in day to day use it’s WORM (write once, read many) without actually going so far as mounting it read only. The data that gets synced daily from my main servers is incremental and usually has few changes.

I’ve had PIs running for years without issue with the SD card mounted read only and retired them from service before the SD cards ever started showing issues. My Meshtastic EAS Alerter project is using one of those Pi Zero W2’s I retired from an older project and its 6 year old SD card.

This is actually the second iteration. Originally I attached a 1 TB SSD via a USB->NVMe enclosure. That worked, but also made the unit sprawl which was something I wanted to trim down in the final version. It worked but had random glitches and instability that I initially chalked up to the board and/or Armbian. I didn’t realize it was EMI from the Wi-Fi coming in through the USB cable until after I switched to the 1 TB SD card. That’s why I added some ghetto shielding to the power cable for lack of having ferrite beads on hand lol.

Should the SD card prove problematic over time, I can always go back to the USB->NVMe solution and lose its “keychain” form factor.

   /_\  _ _ _ __ | |__(_)__ _ _ _  
  / _ \| '_| '  \| '_ \ / _` | ' \ 
 /_/ \_\_| |_|_|_|_.__/_\__,_|_||_|
                                   
 v25.11.2 for BananaPi BPI-M4-Zero running Armbian Linux 6.12.58-current-sunxi64

 Packages:     Ubuntu stable (noble)
 Updates:      Kernel upgrade enabled and 52 packages available for upgrade 
 WiFi AP:      SSID: (BananaAP), channel 6 (2437 MHz), width: 20 MHz, center1: 2437 MHz
 IPv4:         (LAN) 192.168.5.1, 10.10.10.15 (WAN) 192.168.1.12
 Containers:   postgres_postgres_1

 Performance:  

 Load:         4%           	 Uptime:       18 weeks, 22 hours, 49 minutes	 Local users:  2           	
 Memory usage: 45% of 3.83G  	 Zram usage:    74% of 1.91G  	
 CPU temp:     63°C           	 Usage of /:   35% of 29G    	
 RX today:     6 GiB