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I use a Remote Management Module (RMM) (version 4) with my W2600CR2 motherboard for my powerhouse home-office workstation.

I pay for (Gbit fiberoptic) internet service that includes two static IP addresses and one dynamic IP address. The single line carrying the signal that enters the house connects to a switch inside my apartment. On the other side of the switch (the apartment-facing side) are three cables.

  • Static IP #1 leads to the RMM's out-of-band ethernet connection
  • Static IP #2 leads to the workstation's main ethernet connection
  • (And, dynamic IP leads to an unrelated wireless router)

All components of the system, except the wireless router, pass through a surge protector; the surge protector is connected to an uninterruptible power supply (UPS) made by APC.

I use the system by connecting remotely to the workstation through Static IP #2. When necessary, I use the RMM by connecting to the RMM's web console interface at static IP #1 to remotely start or restart the physical workstation.

Recently, the UPS shut down with an F05 error (charge fault), likely caused by a lightning storm leading to a power outage (but I am not sure because I was not on location at the time). I lost contact with the machine - both physical workstation, and RMM.

I arrived on-site yesterday and discovered the F05 fault. In part because the UPS might not be able to be restarted without the company's direct assistance (I am not sure about this because I have not tried yet), but in part because I wanted to get the workstation back up and running before dealing with the UPS, I bypassed the UPS and plugged the surge protector (to which all system components except the wireless router are connected) directly into the wall outlet.

Power immediately returned to the switch and to the workstation. The green/orange steady light started to glow on the ethernet cable plugged into the RMM. Steady green lights appeared on all connections on the switch. (The wireless router, which should be unrelated to this issue, already was powered back on and working, though it did not provide internet access until the switch was powered back on.)

At this point, I expected the RMM to be back online. I expected to be able to start up the workstation using the RMM by accessing the RMM's web console through static IP #1.

However, static IP #1 was inaccessible - it timed out. (Internet access was available through the wireless router, indicating that service was available from the service provider and that the switch was working.)

Finally, I went to the workstation machine, confirmed that the ethernet cable plugged into the RMM was glowing steadily green/orange and that it was fully plugged in. Still, no connection to the RMM via static IP #1.

Here comes the crux of the issue.

I then unplugged, and plugged back in, the ethernet cable to the RMM. The same steady green/orange light reappeared on the physical cable connection. Immediately, static IP #1 became available and access to the RMM's web console was restored and functional (and I was able to use the RMM to power on the workstation).

I would like to understand why I needed to physically remove the ethernet cable from the RMM and plug it back in, in order to restore access to the RMM.

I ask not only from theoretical interest - but also because I am considering purchasing an expensive UPS that provides out-of-band remote access, itself, that allows remote monitoring and control of the power supply to the system, in case this might help stave off power outage issues that shut down the UPS in the future that would otherwise require an on-site visit.

If it turns out that a purchase of such a UPS might prevent the need for an on-site visit in the future in case of a power outage, BUT if the RMM itself does not come back online after power is restored without the ethernet cable itself being physically unplugged and plugged back in, then it's pointless for me to spend the money on a UPS that provides remote access if I still will need to make an onsite visit in order to physically unplug and plug back in the physical ethernet cable to the RMM.

My question is: Why did I need to physically unplug and plug back in the ethernet cable connecting to the RMM after returning power to the switch and workstation by plugging the surge protector into the power outlet? Shouldn't the RMM automatically connect to the internet when power is returned to the system? And, in the future, if I purchase a UPS with remote access, and the same issue happens again, will shutting off power / returning power to the UPS be equivalent to physically unplugging and re-plugging the ethernet cable into the RMM?

Why did the RMM require the ethernet cable to be unplugged and plugged back in? Doesn't this defeat the entire purpose of the RMM - which is supposed to allow me to remotely power on the computer without making an onsite visit?

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1 Answer 1

Lightning and electrical storms can leave systems and especially networking equipment in a funky power state. Believe me, I've experienced it.

All bets are off in the case of an electrical storm, as the issue was probably upstream from your remote-management module (RMM)... Even though you had surge protector and a UPS, It was likely your switch that needed a power-cycle.

In normal conditions, out-of-band devices are still useful.

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Do you think a higher-end, truly "online, double-conversion" UPS (en.wikipedia.org/wiki/… and see cyberpowersystems.com/products/ups-systems/smart-app-ups/…) would make it more likely to avoid lightning surge-related power outage issues in the future? –  Dan Nissenbaum May 25 '13 at 15:54
    
I was using a high-end double-conversion UPS in the lightning situation I linked to in my answer... So I'm not sure... –  ewwhite May 25 '13 at 16:03

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