I’m beautiful and tough like a diamond…or beef jerky in a ball gown.

– Titus Andromedon

  • 23 Posts
  • 147 Comments
Joined 1 year ago
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Cake day: July 15th, 2025

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  • Sadly (and similarly anecdotally) yes.

    Toggling airplane mode basically “turns off and on again” your phone’s network interfaces, resets the routing table, and, I think, flushes the DNS caches. I don’t have the problem so much with wi-fi unless I roam between my main and guest networks which use different DNS records for some of my self-hosted apps. (e.g. the “internal” DNS record gets resolved on main wifi, gets cached, and then is inaccessible on guest wifi until the cached record expires).

    Mainly, I just toggle the cellular data since my primary issue is that sometimes calls/texts stop working without notice.


  • I try for at least 2 hours a day, excluding sleeping.

    Usually that’s in the form of puttering around outside doing yardwork, working on whatever my summer/winter project is, and/or taking the dogs for a walk. It’s difficult in the winter but the other 3 seasons are pretty easy to keep the habit alive

    However you choose to spend that offline time, I highly recommend a daily dose of it. Been doing that for a few years now, and my mental health has improved dramatically. The world isn’t nearly as horrible as social media makes it out to be.


  • 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.











  • This week was nice but we had one last week and one’s forecast for this coming week, though I don’t think it’s going to be as bad as the one we got first week of July.

    Glad I got my PV system installed before the first one hit. A/C just feels cooler when it’s free 😎

    Heatwaves notwithstanding, still prefer summer. I hate shoveling snow, I hate being cold, I hate that people deal with slick roads every year but still can’t learn to drive (or NOT drive) on them, etc. My only complaints about summer are the humidity and mosquitos.



  • 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