Yes, I searched, and then searched again, and again…
I have not used ether1 on my router in the past, used it for PoE in my previous router (changed from a desktop model to rack-mount), but have not it used as an interface.. I need to now.. I am using the power plug on the back right now as well.
Every time I connect ether1 to my switch (C5G124-48P2) ~30 seconds later the router turns off.. Unplug the cable from either end, and the router will boot back up.
My initial thought was the 802.3at switch port might be causing issues with the passive PoE input on ether1.. It shouldn’t, but I disabled the PoE capabilities on the switch port any ways. It is still happening.
Seriously, I plug the Ethernet cable into this router from my switch and 5-10 seconds later it turns off.
Plugging my router directly into the ISP provided modem, everything stays normal.. What am I missing? Any suggestions?
If you connect your router’s ether1 port to gigabit device and it fails, but if you connect this router to 100Mbit device and it’s working, it may be hardware failure. Check diode rectifiers (marked green) and especially check diode (marked red), if it fails, all power from your DC connector flows through ether1 port and short circuited in any gigabit ethernet device. All Mikrotik’s routerboards use the same schematic, and this issue appears on many other models.
I tried adding the RBGPOE, thought if it is a power issue, this might separate (additional diodes?) the power from being passed along.. Unfortunately it had no effect what so ever.
I did notice today that the hosts lose connection with the RB2011, even before it turns off.
Any ideas what I can do to fix or work around this?
You connect a Gigabit POE injector, it will work like generic gigabit port device (you have an issue with that, right?), because it have own transformer to separate power and data, without any kind of “additional diodes”. Try to use a 100Mbit POE injector - it uses 4 pins for data and 4 pins for power, or simply create the cable like this:
Every time I connect ether1 to my switch (C5G124-48P2) ~30 seconds later the router turns off.. Unplug the cable from either end, and the router will boot back up.
My initial thought was the 802.3at switch port might be causing issues with the passive PoE input on ether1.. It shouldn’t, but I disabled the PoE capabilities on the switch port any ways. It is still happening.
Looks like some kind of PoE protection is being triggered.
Are you using shielded cables? Have you tried regular, unshielded cables with unshielded RJ45?
What’s the voltage the enterasys provides via PoE?
I’d try to generate a supout on those 30 sec (or enable System > Watchdog auto supout generation, check supout date to confirm is created) and email support.
In your first post, you didn’t indicate that your modem is gigabit one. So, seems you have a problem with incompatibility of active and passive POE. May you check the voltage at this point:
when you connect ether1 to your switch? If it exceeds 24 Volts, your router will not work. You may try to desolder diode rectifiers (D4, D6) and check if problem persists, but you loose a POE capability of ether1. What happens when you connect switch in other ports of your router? You provide so little information about your problem, remember - nobody knows what are you doing and how do you doing, to resolve your problem - you’ll need to provide maximum information.
Yes, and that is why I am trying to promptly answer every question that is asked, I am not sure what information is needed. With the exception of when I need to take it apart, I can only do that in the late evening here. I indicated in my second post that port 1 was connected at 1 gbps, to another device.
Right now, ports 2-6, 8, and 10 are connected to the same switch.
I will measure the voltage at that point tonight, will also use my multimeter to test the diode.
To recap..
When ether1 connected to my switch ~30 seconds later powers off. Disconnecting the cable in ether1, the modem powers back up and starts booting immediately.
ether2-6, 8 and 10 are connected to the same switch without issue
non-shielded Cat5e and Cat6 cables are being used
Switch is a C5G124-48P2 router is a RB2011-UiAS-RM
Circuit board inside the RB2011 appears ok. Do not see any damaged components.
Writing this out, I am going to try connecting to my 1910-24G-PoE+ switch. I haven’t tried it yet because it isn’t powered on and nothing is connected to it. Also have a C5G124-24P2 switch on it’s way, so don’t plan on using the HP, but is worth testing..
to next device connected to the suspect port ether1, if it’s the internet router, then the internet router IP facing the mikrotik device.
What’s the ROS version and System > Routerboard firmware versions?
I would netinstalll, reset to no defaults and restore the config on the RB2011 in any case, as Support is possibly going to ask you to do the same, ruling out device config corruption, etc.
When I measure that point with ether1 disconnected.. 23.7 volts When I connect ether1 it says at 23.7 volts for ~30 seconds then jumps to 52.6..
If I disconnect the 24 volt power supply, that point to ground drops to 0. If I plug in the RB power supply leaving ether1 connected, that point to ground is immediately 52.6 volts, the router doesn’t attempt to boot.
If I use the RBGPOE injector with the other end to my switch, that point is 51.9 volts, router doesn’t start.
All of this is with the PoE off to this switch port (confirmed with a 802.3af device - no power)
So, the problem with your switch - it wants POE-up your router even when that doesn’t wants it and he’s so stubborn that he doesn’t even listen your commands.
Please don’t shout to your router, it works fine. It just can’t accept so much power, say thanks to mikrotik engineers - they implemented the circuit that protects router from overvoltage. In your situation, without this circuit router would burn.
I think any of these solutions would help you:
[1] Replace your switch to another one without POE.
[2] Try to repair switch.
[3] With help of soldering iron, remove diode rectifiers (D4, D6) from your routerboard.
[4] Do the similar thing as in item 3, but with the switch.
[5] Insert a simple SOHO switch between the devices. BE CAREFUL! Your POE-switch may burn out another switch.
[6] Don’t do anything and continue posting to this topic.
[7] Sell this mikrotik and buy another one with active POE support.
[8] ???
My guess was that the switch was creating a different ground level than the router, or something along these lines… Not sure how to confirm this though. The 30 second delay has me scratching my head though.. It is bugging me the most.
It isn’t supplying power (other devices don’t get powered by the switch) and this switch has zero issues with any other device (close to all 48 ports are used).
If it was supplying power anyways, I would have expected to see the same issue with the PoE-Out port (ether10).
I was thinking about trying a RBGPOE-CON-HP to work around the problem, or a low-tech S-RJ01 adapter…
I may just remove the diodes in the router though.. I am not going to destroy my 48port switch..
Might try and contact Enterasys though.. Supposed to have lifetime warranty, but I suspect they will point to the Mikrotik being at fault..
Might be time for an upgrade though.. The RB1100AHx4 looks nice.. haha
For an update.. I tried another PoE switch, I didn’t disable the PoE on the port, but this time it powers off immediately, not the 30 second delay..
So I have went with option 8.. Connected the switch to the router with SM fiber..
I seriously can not get this switch to improperly send power to any device, except this RB2011.. And I am not even sure it is sending power, or if it is a side-effect of something else.
