Antminer cannot connect through a netgear 3G/LTE modem

[KEBKR]

I have a netgear LB2120 3G/LTE modem.  The modem has a failover switch built in so if the wired internet connection goes down it switches to cellular. I tried connecting my antminers (as well as just one antminer, S9i, L3+, L3++, DR3,) to the modem but for some reason they wont detect an internet connection and will not connect.  I tried connecting the modem to a powered switch and then to the antminer and still no go.  If i plug a laptop in it works fine.  Does anyone know why this may be happening? 

When the antminer is plugged in the lights indicating an ethernet connection are not even lit up but again use the same cable to plug in a laptop and everything works perfect.  I've also tried setting the modem in bridge mode and changing the miner to a static ip etc.  Nothing seems to work as it just doesn't recognize the connection.  Any help is appreciated!

[philipma1957]

I have a netgear LB2120 3G/LTE modem.  The modem has a failover switch built in so if the wired internet connection goes down it switches to cellular. I tried connecting my antminers (as well as just one antminer, S9i, L3+, L3++, DR3,) to the modem but for some reason they wont detect an internet connection and will not connect.  I tried connecting the modem to a powered switch and then to the antminer and still no go.  If i plug a laptop in it works fine.  Does anyone know why this may be happening? 

When the antminer is plugged in the lights indicating an ethernet connection are not even lit up but again use the same cable to plug in a laptop and everything works perfect.  I've also tried setting the modem in bridge mode and changing the miner to a static ip etc.  Nothing seems to work as it just doesn't recognize the connection.  Any help is appreciated!

First question do you know the mining gear works?

Bring one unit to a friends house and see if it connects.

[KEBKR]

First question do you know the mining gear works?

Bring one unit to a friends house and see if it connects.

Yes it works fine as it is just a passthrough device so if i plug the ethernet cable into the miner directly from the home ISP it connects and hashes immediately. Plug the cable from the home ISP into the LTE modem and then onto a laptop that works fine, but plug it into the miner and nothing.

[DireWolfM14]

Does you're modem also have a built in DHCP router, and is the service turned on?  Some do, and some don't.  If you have an old router laying around you could try that, or pick up a used one for cheap off of fleabay.

ETA:

I have a netgear LB2120 3G/LTE modem.

I just looked up the specs on your modem, it doesn't appear to include a DHCP server.  You will need a router, or a computer set up as a DHCP server to provide IP addresses to your miners.  Again, a cheap router is your best bet, and since you don't need it to provide wifi you'll be able to find one that's very affordably priced.

[philipma1957]

get a cheapo asus

https://www.amazon.com/gp/offer-listing/B00DWFPDNO/ref=sr_1_1_olp?

see if it helps

set all to dhcp

your modem
to
asus
to
miner

[BitMaxz]

No, according to the manual of netgear LB2120 it has DHCP server enabled by default.

Take a look at this manual to verify http://www.downloads.netgear.com/files/GDC/LB2120/LB2120_UM_EN.pdf

@OP The modem has two ethernet socket, the Lan and Wan sockets. So, I think you need an extra router for this because it only has one Lan.

Wan is for internet source so you should not plug the miner in this socket.

[KEBKR]

Yes the modem itself can assign DHCP as a router or you can set it to bridge mode which turns this feature off.  I've tried both ways and also tried the miner to DHCP and Static.  Neither of these work. I have the home ethernet connected to the WAN port and the miner to the LAN. The pass through works with a laptop but unplug it from the laptop and into the miner and nothing.  I'll pick up a cheap router as suggested and try that between the modem and the miner just in case.

I tried hooking a cheap router after the LTE modem and so far it seems to be working.  So thanks for that suggestion!  Fingers crossed the failover works as well as I  haven't had a chance to test that yet.  

So in case anyone else tries a similar design, to reiterate my setup is:
A wired connection from my main home router to the LTE Netgear LB2120 Modem into the WAN port.  Then from the Lan port on the 2120 i go to a cheap Dlink router and then on to the antminer.  I have the antminer set to DHCP (not static) with the auto assign DHCP tuned on in the settings of the cheap router.  The 2120 is set to bridge mode and this seems to be working. So now when there's an internet outage the 2120 should auto switch to LTE and the antminers stay connected until the hardwired connection is back online and it will then switch back from LTE to the hardwired connection.

Thanks again everyone for the help.  Cheers!