Restore a CRS328-24P-4S+RM switch after electric black-out stucking at 'jumping to kernel code' visible in console connection.
A couple of years ago I moved to a new flat and set a small rack cabinet to provide four wired network connection to the potential locations of tables and multimedia devices, like TVs, etc.
I chose CRS328-24P-4S+RM as it has PoE capable. This is not an advertisement, but this switch met my expectations in a cost-effective way. My router provided by my Internet Service Provider has been set to bridge mode, my router was an ALIX based IPFIRE firewall appliance due to content filtering regarding to young children. I foolishly didn't install an uninterruptible power supply right away because I was still hesitating about what to buy.
Then once there was a momentary power outage. It was so instantaneous that a desktop computer remained standing.
As a result, my switch apparently died. I could replace it temporarily with an 8 port spare switch,
Then I started to check my Mikrotik switch. It seemed to me that PoE works, but there was no network on ports. Switch has been placed to the lowest self of my cupboard.
I purchase another CRS328-24P-4S+RM. And, of course, a UPS.
Nowadays I had some free time to play with that virtually dead switch.
Findings:
I used an old Cisco console flat (ribbon-like) cable with RJ45 and DSUB9 RS232 plus an ATEN DSUB9 RS232 to USB A male cable as console cable with PuTTY serial connection (in my case COM6 port, 115200, 8, 1, N, RTS/CTS). Console connection showed this:
loading kernel... OK
setting up elf image... OK
jumping to kernel code
And nothing has happened.
Restart again, I pressed any key to get to console config menu.
I chose ‘o’, then ‘e - boot over Ethernet’
I set my laptop’s net interface card IP address to 192.168.88.2, subnet to 255.255.255.0. gateway to 192.168.88.1, I tried to use different versions of netinstall, but my switch did not appear in it. After many-many attempts, netinstall-7.14.3 could recognize my switch.
Of course, I tried the latest routeros-7.14.3-arm.npk to install. Without any success.
Many reboot, many netinstall attempts led to install routeros-arm-6.48.1.npk successfully. Again: in console mode with Netinstall, it was the latest version what I could install.
I had to use console config 'o' to set 'n - boot from NAND, if fail then Ethernet' to prevent continuous attempts of booting from BootTP.
Finally, Winbox could recognize my switch.
OK, let’s it upgrade to latest one. Winbox, Quck Set -> Check For Update showed 6.49.15 only. Man, I could update my new CRS328-24P-4S+RM to current 7.14.3 without any doubt.
OK, let use in Winbox System -> RouterBoard -> Upgrade button and reboot.
The tricky part came here. I downloaded routeros-7.14.3-arm.npk for my CRS328-24P-4S+RM. In Winbox I added it to Files, and reboot device.
I used Winbox System -> RouterBoard -> Upgrade button and reboot again.
Now I have a workable CRS328-24P-4S+RM at the laterst RouterOS:
[admin@MikroTik] > system/routerboard/print
routerboard: yes
model: CRS328-24P-4S+
serial-number: AXXXXXXXXXX4
firmware-type: dx3230L
factory-firmware: 6.43.5
current-firmware: 7.14.3
upgrade-firmware: 7.14.3
[admin@MikroTik] >
A couple of years ago I moved to a new flat and set a small rack cabinet to provide four wired network connection to the potential locations of tables and multimedia devices, like TVs, etc.
I chose CRS328-24P-4S+RM as it has PoE capable. This is not an advertisement, but this switch met my expectations in a cost-effective way. My router provided by my Internet Service Provider has been set to bridge mode, my router was an ALIX based IPFIRE firewall appliance due to content filtering regarding to young children. I foolishly didn't install an uninterruptible power supply right away because I was still hesitating about what to buy.
Then once there was a momentary power outage. It was so instantaneous that a desktop computer remained standing.
As a result, my switch apparently died. I could replace it temporarily with an 8 port spare switch,
Then I started to check my Mikrotik switch. It seemed to me that PoE works, but there was no network on ports. Switch has been placed to the lowest self of my cupboard.
I purchase another CRS328-24P-4S+RM. And, of course, a UPS.
Nowadays I had some free time to play with that virtually dead switch.
Findings:
- PoE was OK, it could power up my PoE devices but without network connection.
- Switch was able to boot for swOS. It is more than nothing but still less than something. Besides, I had absolutely no intention of using it with swOS
I used an old Cisco console flat (ribbon-like) cable with RJ45 and DSUB9 RS232 plus an ATEN DSUB9 RS232 to USB A male cable as console cable with PuTTY serial connection (in my case COM6 port, 115200, 8, 1, N, RTS/CTS). Console connection showed this:
loading kernel... OK
setting up elf image... OK
jumping to kernel code
And nothing has happened.
Restart again, I pressed any key to get to console config menu.
I chose ‘o’, then ‘e - boot over Ethernet’
I set my laptop’s net interface card IP address to 192.168.88.2, subnet to 255.255.255.0. gateway to 192.168.88.1, I tried to use different versions of netinstall, but my switch did not appear in it. After many-many attempts, netinstall-7.14.3 could recognize my switch.
Of course, I tried the latest routeros-7.14.3-arm.npk to install. Without any success.
Many reboot, many netinstall attempts led to install routeros-arm-6.48.1.npk successfully. Again: in console mode with Netinstall, it was the latest version what I could install.
I had to use console config 'o' to set 'n - boot from NAND, if fail then Ethernet' to prevent continuous attempts of booting from BootTP.
Finally, Winbox could recognize my switch.
OK, let’s it upgrade to latest one. Winbox, Quck Set -> Check For Update showed 6.49.15 only. Man, I could update my new CRS328-24P-4S+RM to current 7.14.3 without any doubt.
OK, let use in Winbox System -> RouterBoard -> Upgrade button and reboot.
The tricky part came here. I downloaded routeros-7.14.3-arm.npk for my CRS328-24P-4S+RM. In Winbox I added it to Files, and reboot device.
I used Winbox System -> RouterBoard -> Upgrade button and reboot again.
Now I have a workable CRS328-24P-4S+RM at the laterst RouterOS:
[admin@MikroTik] > system/routerboard/print
routerboard: yes
model: CRS328-24P-4S+
serial-number: AXXXXXXXXXX4
firmware-type: dx3230L
factory-firmware: 6.43.5
current-firmware: 7.14.3
upgrade-firmware: 7.14.3
[admin@MikroTik] >
Statistics: Posted by BazsiBoy — Mon May 27, 2024 12:28 pm