I'm running a RB532, ROS 6.18, FW 2.18
Today I suddenly lost all virtual interfaces (PPoE, VPN, Bridge) only the physical interfaces were there (LAN1, LAN2 ...).
I found out, when I was trying to look at the graphs of my VPN interface and I got a message that the interface doesn't exist.
After a reboot it worked for a while, then happened again.
I also found out, that two of my static routing rules stopped to work, they are blue now in the Winbox route list.

I have tried upgrading to ROS 6.19 and it happened again (loss of virtual interfaces).
So I downgraded back to ROS 6.18.

The RB532 was running for 40 days without a problem and I didn't change anything before it happened the first time.

What could be the problem?

NAND failing?
901 464 total sectors written, 0.2% bad blocks

Bad PSU? 18V 1A

Any other ideas?

I think I can rule out the PSU, changed for another one and the issue is still happening.

I found out I can provoke the issue by doing something in Winbox - opening windows, etc, no changing of any configuration.

One more thing - I noticed when it happens, the WLAN interface is gone too.

After numerous netinstalls of ROS 6.18 and 6.19 I'm thinking, that the flash is really dying.

The RB is still behaving strange:
- I exported the config, that I imported after netinstall and compared the two - there are letters missing in the export file
- the two mentioned static routes sometimes work sometimes don't and are blue in the Winbox route list
- many times the first attempt to login is rejected (bad password or username), then the second attempt with same credentials is accepted (even from serial console)
- I'm not able to connect with Winbox the the IP, only to the MAC address
- every couple of hours a suppout file is generated
- the RB doesn't work reliably - obviously

I don't know how big a sector on this flash is, so I don't know how data written the 901 464 sectors represent.

Possible solutions:

1) format NAND from BIOS, but that means erasing the licence and I'm not sure it would solve the problem

2) Install ROS on a CF card, but it seems that it isn't possible and even if it was, I would need a new licence

3) Workaround - install OpenWRT or something like this on a CF card

Any ideas or suggestions?