GS108 (not POE) will not transfer data to POE injector

[spyker_dot_net]

We have recently updated the cabling in our offices and are connecting all our PCs and other network devices to the new ports.  In doing so we found the need to purchase a couple of unmanaged switches to handle the sharing of the connection at some of our workstations.  We have VOIP phones and most of them have functioning pass through ports that allow the PCs and phones to share the connection without a switch.  On the ones which don't we have a POE injector that is connected to the phone and the Netgear GS108.  This setup has been tried with a couple of workstations without success.  The first one I was able to bypass the switch and plug directly into the wall because the main switch is POE enabled.  The second workstation phone does not have a functioning pass through port thus the need for the switch so that we can share the connection with the PC and the phone.  Though the PC gets full access to the network and the phone gets power via the POE the Netgear will not serve data through the POE injector and the phone, though powered, can't access the network.  I tried a CAT 5e cable connected to an old 10/100 Cisco Linksys switch (not POE enabled) and that one worked.  Thinking it might be the cable I tried that cable with the Netgear GS108 and the POE injector and it did not work.  So for whatever reason the Netgear is refusing the communicate with the POE injector device.  I really don't want to keep the old unmanaged Cisco switch, but I may have to so that the phones keep working.

[schumaku]

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@spyker_dot_net wrote:

So for whatever reason the Netgear is refusing the communicate with the POE injector device.  I really don't want to keep the old unmanaged Cisco switch, but I may have to so that the phones keep working.

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The POE Injector would start to provide power when plugged, and the connected PD would come up and establish a PHY Ethernet link with the switch. With the device not coming up with a link, there won't be communications. this happens in two steps.

[spyker_dot_net]

The POE injector is plugged in and very obviously providing power to the PD. Why though is the data not flowing through from the Netgear GS108 but when it's plugged into the Cisco Linksys under identical conditions the data flows through and the PD works fine? What is the Netgear device not doing that the Cisco is? How can I alleviate it? Do i just have a defective device?

[schumaku]

Some products notoriously fail in the auto-negotiation, an optional function of the IEEE 802.3u Fast Ethernet standard that enables devices to automatically exchange information over a link about speed and duplex abilities. The connected devices first share their capabilities regarding these parameters and then choose the highest performance transmission mode they both support. It's defined in clause 28 of IEEE 802.3 and it was originally an optional component in the Fast Ethernet standard.is backwards compatible with the normal link pulses (NLP) used by 10BASE-T. The protocol was significantly extended in the Gigabit Ethernet standard, and is mandatory for 1000BASE-T gigabit Ethernet over twisted pair. This is still causing interesting finger-pointing sessions between support departments of the vendors in the year 2023.

Can we have "GS108" (serial, exact designation on the label, like v1, v2, v3) and "Cisco Linksys PoE Phones" in a little bit more detail? Or re we talking about the GS108E v1, v2, v3 plus switches?

A common workaround I'm suggesting in other communities on Ethernet not establishing a link is what you have already done: Get some random non-managed low-cost switch and link it in between the two subject devices.

Sure, a hardware replacement on either end can often magically  "resolve" the incompatibility or interoperation issue.

I'd suggest to talk to the support organizations of both vendors - they often know their "kids" well. 

Regards

-Kurt

[spyker_dot_net]

ProSAFE 8 Port Gigabit Unmanaged Switch (GS108v4)

Serial Number: 6A3xxxxxxxxxx

Tried to contact Netgear support without success. Have had the item in office new since May, but was just opened and installed last week.