This article explains how to convert QFX5120-48Y-8C to EX4650-48Y-8C.
The 'show chassis hardware'
command displays QFX5120-48y-8c instead of EX4650-48Y-8C.
root@SW> show chassis hardware
Hardware inventory:
Item Version Part number Serial number Description
Chassis AAABBBCCCDDD Virtual Chassis
Routing Engine 0 BUILTIN BUILTIN RE-EX4650-48Y-8C
Routing Engine 1 BUILTIN BUILTIN RE-QFX5120-48Y-8C
FPC 0 REV 09 650-083242 AAABBBCCCDDD JNP48Y8C-CHAS
CPU BUILTIN BUILTIN FPC CPU
PIC 0 BUILTIN BUILTIN 48x25G-8x100G
FPC 1 REV 09 650-083242 AAABBBFFFGGG JNP48Y8C-CHAS
CPU BUILTIN BUILTIN FPC CPU
PIC 0 BUILTIN BUILTIN 48x25G-8x100G
root@SW> show virtual-chassis
Virtual Chassis ID: da9b.66a1.a7bd
Virtual Chassis Mode: Enabled
Mstr Mixed Route Neighbor List
Member ID Status Serial No Model prio Role Mode Mode ID Interface
0 (FPC 0) Prsnt AAABBBCCCDDD ex4650-48y-8c 255 Master* N VC 1 vcp-255/0/54
1 vcp-255/0/55
1 (FPC 1) Prsnt AAABBBFFFGGG qfx5120-48y-8c 250 Backup N VC 0 vcp-255/0/54
0 vcp-255/0/55
{master:0}
root@SW> request system software add /var/tmp/jinstall-host-ex-4e-x86-64-18.4R1-S2.4-secure-signed.tgz force-host member 1
Verified jinstall-host-ex-4e-x86-64-18.4R1-S2.4-secure-signed signed by PackageProductionEc_2019 method ECDSA256+SHA256
Pushing Junos image package to the host...
Installing /var/tmp/install-media-qfx-5e-junos-18.4R1-S2.4-secure.tgz
Extracting the package ...
============================================
Host OS upgrade is FORCED
Current Host kernel version : 3.14.52-rt50-WR7.0.0.9_ovp
Package Host kernel version : 3.14.52-rt50-WR7.0.0.9_ovp
Current Host version : 3.1.0
Package Host version : 3.1.0
Min host version required for applications: 3.0.7
============================================
Validate linux image...
upgrade_platform: -------------------
upgrade_platform: Parameters passed:
upgrade_platform: silent=0
upgrade_platform: package=/var/tmp/tmp.l4dc1kjziOjunos_cli_upg/jinstall-qfx-5e-junos-18.4R1-S2.4-secure-linux.tgz
upgrade_platform: clean install=0
upgrade_platform: on primary =0
upgrade_platform: clean upgrade=0
upgrade_platform: Need reboot after staging=1
upgrade_platform: -------------------
upgrade_platform:
upgrade_platform: Checking input /var/tmp/tmp.l4dc1kjziOjunos_cli_upg/jinstall-qfx-5e-junos-18.4R1-S2.4-secure-linux.tgz ...
upgrade_platform: Input package /var/tmp/tmp.l4dc1kjziOjunos_cli_upg/jinstall-qfx-5e-junos-18.4R1-S2.4-secure-linux.tgz is valid.
Secure Boot is enforced.
ALLOW:usr/secureboot/grub/BOOTX64.EFI
ALLOW:boot/bzImage-intel-x86-64.bin
ALLOW:boot/initramfs.cpio.gz
Setting up Junos host applications for installation ...
Current junos instance is 0
Installing Host OS ...
upgrade_platform: -------------------
upgrade_platform: Parameters passed:
upgrade_platform: silent=0
upgrade_platform: package=/var/tmp/jinstall-qfx-5e-junos-18.4R1-S2.4-secure-linux.tgz
upgrade_platform: clean install=0
upgrade_platform: on primary =0
upgrade_platform: clean upgrade=0
upgrade_platform: Need reboot after staging=0
upgrade_platform: -------------------
upgrade_platform:
upgrade_platform: Checking input /var/tmp/jinstall-qfx-5e-junos-18.4R1-S2.4-secure-linux.tgz ...
upgrade_platform: Input package /var/tmp/jinstall-qfx-5e-junos-18.4R1-S2.4-secure-linux.tgz is valid.
Secure Boot is enforced.
ALLOW:usr/secureboot/grub/BOOTX64.EFI
ALLOW:boot/bzImage-intel-x86-64.bin
ALLOW:boot/initramfs.cpio.gz
upgrade_platform: Staging the upgrade package - /var/tmp/jinstall-qfx-5e-junos-18.4R1-S2.4-secure-linux.tgz..
./
./grub/
./grub/grub.efi
./grub/grub.conf
./initramfs.cpio.gz.psig
./upgrade_platform
./bzImage-intel-x86-64.bin.psig
./bzImage-intel-x86-64.bin
./initramfs.cpio.gz
./host-version
./initrd.cpio.gz
./version.txt
./platform_info
./linux.checksum
bzImage-intel-x86-64.bin: OK
initramfs.cpio.gz: OK
version.txt: OK
upgrade_platform: Checksum verified and OK...
1067228 blocks
upgrade_platform: Staging of /var/tmp/jinstall-qfx-5e-junos-18.4R1-S2.4-secure-linux.tgz completed
upgrade_platform: System need *REBOOT* to complete the upgrade
upgrade_platform: Run upgrade_platform with option -r | --rollback to rollback the upgrade
Host OS upgrade staged. Reboot the system to complete installation!
{master:0}
root@SW> request system reboot at now
Reboot the system at now? [yes,no] (no) yes
*** FINAL System shutdown message from root@SW ***
System going down IMMEDIATELY
root@SW> show chassis hardware
Hardware inventory:
Item Version Part number Serial number Description
Chassis AAABBBCCCDDD Virtual Chassis
Routing Engine 0 BUILTIN BUILTIN RE-EX4650-48Y-8C
Routing Engine 1 BUILTIN BUILTIN RE-EX4650-48Y-8C
FPC 0 REV 09 650-083242 AAABBBCCCDDD JNP48Y8C-CHAS
CPU BUILTIN BUILTIN FPC CPU
PIC 0 BUILTIN BUILTIN 48x25G-8x100G
FPC 1 REV 09 650-083242 AAABBBFFFGGG JNP48Y8C-CHAS
CPU BUILTIN BUILTIN FPC CPU
PIC 0 BUILTIN BUILTIN 48x25G-8x100G
Factory default image (device shipped with this image) or when the device does not have the EX4650-48Y-8C tag or if the process was previously completed by another user.

To resolve this issue, install the EX4650 image using the force-host command.
Example:
>request system software add /var/tmp/jinstall-host-ex-4e-x86-64-18.3R1.11-secure-signed.tgz force-host reboot