The device generated minor error as below:
Root@SRX5400-> show system alarms
node1:
--------------------------------------------------------------------------
1 alarms currently active
Alarm time Class Description
2025-12-25 12:36:56 CST Minor Host 0 Boot from alternate media
{primary:node1}
root@SRX5400> request system snapshot node 1 partition media compact-flash
error: compact-flash media missing or invalid
The SRX5k RE-1800X4 routing engine boots from the storage media in this order: the USB device (if present), the CompactFlash card, the solid-state drive (SSD), and then the LAN. Normally, the firewall boots from the copy of the software on the CompactFlash card.
root@SRX5400> show chassis hardware detail no-forwarding
Hardware inventory:
Routing Engine 0 REV 05 xxxxxxxxxx xxxxxxxxxxx SRX5k RE-1800X4
ad1 114304 MB VSFA18PI128G-KC xxxxxxxxxxx Disk 1
----------------------------------------- Compact Flash storage is missing here
usb0 (addr 1) product 0x0000 0 vendor 0x0000 uhub0
usb0 (addr 2) product 0x0020 32 vendor 0x8087 uhub1
DIMM 0 VL31B5463F-F8SE-KC DIE REV-0 PCB REV-0 MFR ID-ce80
DIMM 1 VL31B5463F-F8SE-KC DIE REV-0 PCB REV-0 MFR ID-ce80
DIMM 2 VL31B5463F-F8SE-KC DIE REV-0 PCB REV-0 MFR ID-ce80
DIMM 3 VL31B5463F-F8SE-KC DIE REV-0 PCB REV-0 MFR ID-ce80
On this device, since the RE compact flash card is missing and can't be detected, so when device rebooted, it will boots from the secondary storage(SSD). That's why the system reported minor error "Host 0 Boot from alternate media" and why the snapshot to CF operation can't be success.
Since SRX5k RE-1800X4 CompactFlash card is fixed and is inaccessible from outside the device, the only way to fix this issue is RMA for the routing engine.