EM7455 ping timeout in uplink direction

Hello, all

I try to use EM7455 with QMI SDK Connection_Manager.
The result of Call Status is “CONNECTED”, but ping is timeout.

When I ping to the default gw, the TX packet of ifconfig is counted,
but the RX packet is not counted. When I monitor LTE radio, data is not

On the other hand, ping to EM7455 from internet is passed. :question:
Both the TX packet and RX packet of ifconfig are counted.

Does the EM7455 have routing function?
Does anyone know why ping only does not pass in uplink direction?


The default GW does not exist. It’s a fake to satisfy the host system, emulating a L3 subnet assigned to an ethernet. It reality, the modem is connected to the PGW via a point-to-point link, and is assigned a single address only. The address you see as “GW” is most likely one of hte other PGW pool addresses, and may be in use by another modem. Or currently not in use at all. In any case, you cannot expect it to respond to pings.

Try pinging some address on the Internet which you know will respond to pings instead. My guess is that it works.

I solved it.
After I chageed the OS, ping came to pass!

I test by connecting to the simulator.
I pinged a real machine, but pig does not pass.

So, when I changed form CentOS 6.9 to bunutu 9.10,
ping came to pass.

Thanks for help.