SG110D-05 Switches

[piclement]

I recently bought two SG110D-05.

I installed one in a brand new environment. There is a laptop, a computer and a printer connected to it. Everything works fine with that one. The cabling goes to a SG112-24-NA switch, which in turn, is connected to a Cisco Router 881 (C881-K9). So all equipment is brand new and, if I'm not mistaking, all running at 1Gbps. In any case, all is well.

The other one I use in an older environment and a PC, a printer and a server were connected to it. Everything worked fine at first but not for long. This switch is connected directly to the router (an old Bell Canada router). Not even after an hour, the client called to say that nothing was working. I asked him to unplug the switch and plug it back it. Everything started working again. Next morning, same thing. This time, I went myself to the office. I noticed that even though nothing was plugged in port #3, that light was flashing. I installed an old switch I had in stock and brought the new Cisco switch to my office. Everything has been working fine for my client since then. So, I know the problem was the switch.

After a few days, I connected the power to the switch in my office and left it there to work on it later. Even though, I hadn't plug anything in it (except the power), when I came in the next morning, I notice that, again, port #3 light was flashing. See the attached photo .... It's flashing really quickly and the only way to make it stop, is to turn off the switch and restart it. I called tech support and, after discussion, they sent me an RMA. So, I proceeded to sent them the faulty switch and wait for its replacement.

I got the replacement today. I plugged it my office and plugged in a printer with it. Sent something to the printer and everything was fine. After a while, people started complaining that the Internet wasn't working anymore. I went into the room where the switch was installed and, yes, the light on port #3 was flashing also on this "new" switch I got from Cisco. It's not the same serial number, so I don't think they sent the same switch back to me. As soon as I turned off the switch, everybody had access to the Internet again. Nobody was connected to the switch directly (except the printer) but they were connected by wifi to the router where the switch was connected.  When I turned off the switch, I didn't do anything to the router and everything was working again.

So, did I get another "bad" DOA switch ? I don't think there is any firmware I can update on these switch. Right ? Since, the other one is working with brand new equipment and all at 1Gbps, I'm starting to believe that this switch doesn't work well with older equipment and a mix and match of 1Gbps and 100Mbps. After a while, it looks like the communication doesn't go through properly with the switch and it goes "bonkers".

Any suggestion ?

Thanks !

[josh.lee1]

We also purchased a batch of these same switches (20). We contacted cisco, they asked us to do some further testing (isolating the switch from our enterprise network). We did, and our test proved that it does not take very long for the switch to lock up and loose connectivity, we did discover once the switch goes to a blinking light on port 3, that if you plug in a device to the port, connectivity is restored.

Email chain to cisco support is below.

Josh,

I will double check to see if there is anything that I can do, and at the least report the issue itself, however I do not know how much use this will be for you in a short period of time. We always appreciate information, and although I would like to troubleshoot more, I would not ask you to hold the units over any return period with your vendor that you may have. If you are in need of a working switch and the SG110 series is not providing that, then it may be best to return them for something that will. I will check again to see if there is anything I can do on my end and report the issue as well, but again I am not sure it will be something that is timely. I do apologize for any inconvenience this has caused you and I am very thankful for the information.

On 9/29/2015 7:32 AM, Lee, Josh wrote:  -

We did some further testing and the problem is still with the Cisco Mini Switch, we removed the uplink tied 2 computers to the switch with static IP’s and did a continuous ping until the switch failed. The switch failed multiple times. We do notice during a switch failure a green flashing light comes on a port with nothing plugged into it. The other observation was if we plug  another device into the mini switch once connectivity is lost, connectivity is restored, almost seems like an electrical issue or something. We have had the same results on multiple new 110 series switches. I can send you a video of the blinking lights when a failure happens  if you would like, please let me know the best way to upload or send that over. We need to get a resolution, or a return started which I’m assuming needs to go back to our vendor.

Thank you for the follow up.

[Chadster766]

IMO these small switches are defective from the plant. I wish I had a picture of when I moved an Ethernet cable from one port to another and it continued to flash activity like it was a hub on the empty port.

[Chadster766]

These little switches malfunction and can take down your network! I bought three and deployed two with a 100% failure rate. Theses three new small switches will be returned as defective.

[piclement]

I called Cisco Support again. They asked if I would like to receive a 16 ports switch instead and, since this was my 3rd try with them, they proceeded with an advanced RMA. I received the 16 ports switch the next day and sent back the 5 ports switch. I'm not touching those again.

[Chadster766]

Thats awesome I've always liked Cisco support.