Downgrade from 6.15 to 5.12 on 911-5Hn

RouterOS General
1

hello

I have 2 911-5Hn boards that corrupted when downgrading from 6.15 to 5.12.

They still show a network connection but they do not get detected by winbox nor do they show up in any lan scans

These boards do not have a serial connector so I cant serial into them and fix the corruption.

I did notice that they have pinouts for jtag connection

can I build a jtag connector and serial into these boards

Any Ideas on how to recover them.

Obviously I have tried the reset button

2

use netinstall.

and why you want put 5.12???

3

I don’t think they even support version 5.x.
In general you should not downgrade to a version lower than it was shipped with. This is also true for Cisco and other manufacturers.

4

5.12 is not supported on rb911. You can try 5.26

5

Hello

Thank you for the replies


perhaps I was not clear in my OP.

The boards no longer reply to any scans even though windows sees a network connection.

Do I not need a serial connection to use net Install??

I wanted to go to 5.12 because I found it to be the most stable version after 4.17


Why would 5.26 work but 5.12 not work the changes between the two versions are minor?

Now I am seeing other posts where 912 and 911 boards are not responding after upgrades.

there is OBVIOUSLY a problem with these boards and changing the router OS version. soooooooooooo

back to my original question…can I use a j-tag programmer to reload an uncorrupted version of router OS.

Does anyone have the software to do this?

MIKROTIK will you provide j-tag software so we can fix this problem ourselves???

6

It was answered why you can’t use v5.12 with this device. This is because when v5.12 was compiled the 911-5Hn did not exist as a device and the os doesn’t support it.
Here is a full description of the Netinstall procedure :

http://wiki.mikrotik.com/wiki/Manual:Netinstall

You don’t need any special cables for that. If done properly your device will be usable again, but not if you try to netinstall it with old version again.

7

Hello

I am fully aware how to use netinstall …on boards that have serial connectors…

Perhaps I am stupid but it is my understanding that Netinstall needs a serial connection to the board and the computer.

911 boards do not have a serial port.

They do however have a place to wire in a J-tag programmer hence my other question.

8

NETINSTALL USE ONLY ETHERNET PORT