I have configured a router board rb133 and the the settings go back to factory defaults when it reboots? what could be the reason for this
George Mida

Normally, that is a key challenge. My RB133 lost its key due to low supply voltage, and it did the same thing. It also will not hold the settings for more than 24 hours until you enter a valid key. If the box had a valid key before, contact your dealer, and they will issue you the key again.

when i look at the license it still shows? unless there is another way of showing validity

Just to make things clear, the "/system license software-id" is not the key.
/system license output
will create a file in "/file" with the software-id as the file name and ".key" as the extension. You should be able to see the key with
/file print detail

As I recall, the key status is also reported on bootup using the serial console terminal.

this is true the key does not exist in the file menu. why could this happen and any idea on recitifying the situation?
midia

The key file will not appear until you run
/system license output

I do not know all the reasons the MT boxes lose the key, but my loss was due to low supply voltage. I use marine deep-cycle batteries for power backup. I had failed to connect one to the Low Voltage Disconnect on the charge controller, so during a power failure and the battery slowly died, the rest of the boxes were disconnected at 11 volts. But not one. I had failed to connect it to the LVD terminal, and instead was connected directly to the battery. During the power outage, the battery got down to about 8 volts. When they say 10 volts is the minimum supply voltage, they are serious!

the power could be the issue look at below logs almost all are power outages which could have resulted to the loss
(44 messages not shown)
jan/01/1970 00:00:36 system,error,critical router rebooted without proper shutdo

w
n, probably power outage
jan/01/1970 00:00:40 system,error,critical router rebooted without proper shutdo

w
n, probably power outage
jan/01/1970 00:00:40 system,error,critical router rebooted without proper shutdo
w
n, probably power outage
jan/01/1970 00:00:35 system,error,critical router rebooted without proper shutdo
w
n, probably power outage
jan/01/1970 00:00:36 system,error,critical router rebooted without proper shutdo
w
n, probably power outage
jan/01/1970 00:00:36 system,error,critical router rebooted without proper shutdo
w
n, probably power outage
jan/01/1970 00:00:36 system,error,critical router rebooted without proper shutdo
w
n, probably power outage
jan/01/1970 00:00:26 system,error,critical router rebooted without proper shutdo
w
n, probably power outage

[admin@IS] > sy


Midia

Yes, sir! That be a power problem! Check your supply voltage with a voltmeter to insure all is well.
Remember, high voltage can be as fatal as low voltage. I have seen 24vdc wall warts put out as much as 30 volts with an inadequate load. Try to use a power supply with the current rating as close to what you need as practical. I use 12vdc 500ma power supplies for testing.

ADD: Forgot to ask. How many and what type of radios do you have on it? Maybe overloading the internal supply if loaded with high-power radios. Just from memory, the SR2 uses about 3.3v 1300ma when transmitting at its max power. 800ma at idle. So it may even boot ok, but when the radios start to transmit...

FYI, the log entries above can also be attributed to unplugging the power without shutting down.

ADD2: And don't check the p/s without a load. If you want to see what the board is getting, check the RB133 fan output. It is unregulated. It will show the supply rail voltage while under load.