RB951U POE Out Incompatible With Metal 2SHPn? - Won't Power

Hardware MikroTik hardware general
1

Hello,

We have 951U as client routers, and using Metal 2SHPn as CPE devices. When enabling the POE on port 5 to either Auto On, or Forced On, The red LED just blinks every 3 seconds or so after a reboot. We’ve tested different cables, and different 951’s and 2SHPs (we have about 15 we are trying to install) and they all do the same thing. Putting a current meter on the cable only indicates about 100-115ma of current during the boot process of the Metal. We’ve seen posts of other having this issue, and suggestions to downgrade to 6.17, however, the problem continues with all older versions we have tried. Powering a Groove 25 works just fine with the same ROS level. Leaving the unit in this mode, (blinking red LED) yields something on the board overheating, as we begin to smell hot components. This has been reproduced on 3 951 units from the same batch. This batch mac addresses end with a /435. We tested on a 951 unit from batch /348 and it experiences the same issue.

Model 951Ui-2HnD
Serial Number 4AC804B960EF
Current Firmware 3.19
Upgrade Firmware 3.19

The Metal batch numbers end in /438 that are problematic. We located an older Metal, with a batch number of /342 which will boot up fine with the newer 951Us. This makes us wonder if the Metals we received have a different chip set, or ethernet chip that is not being sensed by the power circuit in the 951 correctly, or they are just defective.

Model Metal 2SHPn
Serial Number 590004D8DDD0
Current Firmware 3.21
Upgrade Firmware 3.21

If we allow the unit to boot, without the Metal CPE in port 5, and then insert the POE cable, it will sometimes power up. However that is a problem if the units lose power. Having the customer remove/replace the cable is not a good solution. If we remove the cable from port 5 while the red led is blinking, wait, then plug the cable back in the Metal will sometimes power up fine.

It appears that during boot, the auto-on circuit gets confused and begins a teeter-totter of on/off from a power up boot until the cable is removed and replaced.

Is this a hardware problem that we should return the batch of equipment? Or is there a known way to make the POE port support the device on boot. The specs say up to 500ma of current, and we are powering the 951U with a 2.5A power supply and still see the problem.

We tested with a Map2n and it will power the Metals up fine, both via the RouterOS switch, and after a reboot. It is running version 3.17 of the bootloader.

Please advise as to a solution.

Thank You!!

2

We continue to see this issue, and now with Metals and OmniTiks as well. Here’s video of issue, and serial numbers of non working units.

We are RMA’ing about 3 units a week that exhibit this behaviour.

Here is a video of the issue:
https://dl.dropboxusercontent.com/u/9149975/MikroTik_Test.mp4

Today, 3 Metals exhibited the same boot up issue on OmniTik5UPAs as well. This seems to be a power up issue with the boot sequence of recent hardware.

Here are the serial numbers of 951s and Metals recently returned due to this issue.

RB951Ui-2HnD bad poe out port5
4AC70432C533/435 MAC: 4C:5E:0C:B0:58:7A


RB951Ui-2HnD bad poe out port5
MAC: 4C:5E:0C:B3:28:04 4AC704DB680A/435


RB951Ui-2HnD bad poe out port5
MAC: 4C:5E:0C:78:DE:EC 4AC70486828B/433


METAL 2SHPn
will not pwr up through RB951Ui
590004BEA168/445 (ETH1 MAC: 4C:5E:0C:89:52:28)

METAL 2SHPn
will not pwr up through RB951Ui
59000430F1B7/445 (ETH1 MAC: 4C:5E:0C:89:6C:79)

METAL 2SHPn
will not pwr up through RB951Ui
51D70446C292/434 MAC: 4C:5E:0C:84:76:D9

3

Just tested it with /433 RB951Ui and /445 Metal2 and it works for me. Both are v6.27 with 3.22 firmware with absolutely no configuration. Used 12V 0.5A power adapter for RB951Ui and 100 meter long ethernet cable for Metal. Have you tried a different power adapter?

[admin@MikroTik] > in et poe pr
                      name: ether5
                   poe-out: auto-on
              poe-priority: 10
  power-cycle-ping-enabled: no
      power-cycle-interval: none

Can you also check this serial number? It seems to be invalid:

MAC: 4C:5E:0C:78:DE:EC 4AC70486828B/433

4

Yes, we have checked multiple power supplies. As indicated, this also manifests itself on Metals and OmniTiks as well. It is erratic, in that some times it will work after 5-10 attempts. It’s clearly a race condition of some sort, or some component of hardware clamping on the boot sequence. What does the flashing Red mean? Did you review the video? You can see that unplugging the Metal, then plugging in, resolves, but that is an issue if the unit loses power. We are using this combo for Public WiFi for the State of Idaho, and power cycles happen regularly.