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I have an USB 3G modem (Huawei E353-u2) on pfSense 2.0.2 (which is based on FreeBSD 8.1-RELEASE-p13), it seems to create 2 /dev/cuaU devices:

/dev/cuaU0.0
/dev/cuaU0.3

1) Why are there 2 devices? Is one of them maybe the usb mass storage of the stick?

2) On the OS level (shell), how can I find out which of those 2 devices is the "real modem" / to what /dev/cuaUx.y is mapped?

Thanks for any hint :-)

stefan.at.kotlin
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  • `dmesg | grep cua` tells you what? ;) . If you know the manufacturer you could grep for it too: `dmesg | grep -i Huawei `... –  Dec 12 '13 at 17:08

2 Answers2

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The CUA devices are both serial ports. 3G modems have often 1 to 3 serial ports. One of them is the communication port and the rest are control and monitor ports that you can use for e.g. checking the signal level (with AT commands) while connected.

The first port is almost always the communication port that you should use.

You can see if dmesg gives any hint on which port is which, but most likely only the modem knows and Huawei won't tell.

jkj
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1

Web search suggests this modem knows AT command set, so you can easily check this using "tip" or "cu" commands with both ports and detect which one responds to AT.

Netch
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