You can use this procedure to recover a Routing Engine that fails to boot because of PR:1911820.

A Routing Engine does not boot. The system appears to be non-responsive at the console.

1. Remove and Re-insert the Routing-Engine to re-establish the hung console connection to the RE.

2  Await for the GNU GRUB menu and press e to edit the boot parameters for entry labeled as  “Serial console efi_P” shown below (refer the screenshot below)

3. Add "vjunos-console=telnet" to the setparams menu for "Serial console efi P" at the end of the line of linux/vmlinuz as show below. Press ctrl-x or F10 to login to the Linux host.

linux /vmlinuz root=LABEL=jrootb_P ro quiet efi=runtime pcie_port_pm=off li\|
|bata.force=noncq ${isolcpus_list} enforcing=0 pci=resource_alignment="00:1f\|
|.3;09:0d.0"  rootdelay=5 unknown_nmi_panic=1 ro max_loop=255 quiet efi=runt\|
|ime console=${console_string} crashkernel=512M ${maxcpus_no} ${diag_kcmd_pa\|
|rams}  acpi_enforce_resources=lax vjunos-console=telnet  

4. Approximately after 10 minutes, the login prompt appears for the host Linux, log in as "root". The password is the same as it was set under Junos system "root-authentication" configuration.

5. Uncomment the line "#tls_no_sanity_certificate = 1" in the /etc/libvirt/libvirtd.conf file using the following command:

sed -i -E 's/^[[:space:]]*#?[[:space:]]*(tls_no_sanity_certificate =).*$/\1 1/' /etc/libvirt/libvirtd.conf

6. Verify that the "tls_no_sanity_certificate = 1" is uncommented correctly:

root@router-re0-node:/cat /etc/libvirt/libvirtd.conf | egrep 'tls_no_sanity

tls_no_sanity_certificate = 1

7.  Verify that the disabling of TLS certificate check is done properly to ensure libvirtd. service starts even with the expired certificat. You can use the following command to restart libvirtd

systemctl restart libvirtd

8. Verify libvirtd is running using the:

systemctl status libvirtd

The output should show that the libvirtd is "active (running)". Here is a reference output with libvirtd

systemctl status libvirtd
● libvirtd.service - Virtualization daemon
  Loaded: loaded (/lib/systemd/system/libvirtd.service; disabled; vendor prese>
Drop-In: /etc/systemd/system/libvirtd.service.d
          └─override.conf
  Active: active (running) since Sat 2026-10-10 00:23:58 UTC; 43min ago
    Docs: man:libvirtd(8)
          https://libvirt.org
Main PID: 8244 (libvirtd)
   Tasks: 34 (limit: 32768)
  Memory: 441.2M
...

9. Reboot the system with the "reboot" command at the shell prompt

First publication 2025-10-14