I have my Pi 4B set up so that it boots from an external SSD connected via one of the USB-A ports. The boot order is set such that it should **only** ever attempt to boot from the SSD:
I also have a microSD card inserted in the usual slot, this is a simple exfat-formatted microSD that I want to use as removable storage.
If I try to boot up my Pi whilst this SD is inserted into the Pi, it refuses to boot and I cannot SSH into it. If I turn the power off, remove the SD, then power it back on, it boots from the SSD without issue. If I then insert the SD card in once the system is booted, the card works just fine:
Why does the insertion of a microSD card seem to mess with the boot process when I have explicitly excluded the microSD from the Pi's boot order by removing `0x1`, and how can I use my Pi with the microSD inserted but prioritising boot from the SSD?
Code:
λ rpi-eeprom-config [all] BOOT_UART=0 WAKE_ON_GPIO=1 POWER_OFF_ON_HALT=0 DHCP_TIMEOUT=45000 DHCP_REQ_TIMEOUT=4000 TFTP_FILE_TIMEOUT=30000 TFTP_IP= TFTP_PREFIX=0 BOOT_ORDER=0xf4 [none] FREEZE_VERSION=0If I try to boot up my Pi whilst this SD is inserted into the Pi, it refuses to boot and I cannot SSH into it. If I turn the power off, remove the SD, then power it back on, it boots from the SSD without issue. If I then insert the SD card in once the system is booted, the card works just fine:
Code:
λ duf │ 3 local devices │ │ MOUNTED ON │ SIZE │ USED │ AVAIL │ USE% | TYPE │ FILESYSTEM │ │ / │ 467.9G │ 235.9G │ 208.2G │ ██████████ 50.4% │ ext4 │ /dev/sda2 │ │ /boot/firmware │ 511.0M │ 78.2M │ 432.8M │ ███ 15.3% │ vfat │ /dev/sda1 │ │ /media/frey/RPISD │ 238.7G │ 133.5G │ 105.2G │ ███████████ 55.9%│ exfat │ /dev/mmcblk0p1 │Why does the insertion of a microSD card seem to mess with the boot process when I have explicitly excluded the microSD from the Pi's boot order by removing `0x1`, and how can I use my Pi with the microSD inserted but prioritising boot from the SSD?
Statistics: Posted by Freymotifs — Mon Dec 15, 2025 11:53 am — Replies 0 — Views 35