Huawei E173s

This page describes how to set up Huawei E173s 3G USB modem on Arch Linux.

Check modem

Plug in the modem and install usbutils (base):

pacman -Sy usbutils

Run lsusb:

lsusb

The output should be something like this:

Bus 003 Device 003: ID 12d1:1c0b Huawei Technologies Co., Ltd.

The ID 12d1:1c0b refers to vendor id and product id. If you get different values, it means your modem is not Huawei E173s (of course, you can always open the USB stick to double check).

Set up usb_modeswitch

Install usb_modeswitch (community):

pacman -Sy usb_modeswitch

Create a configuration file for your modem:

nano /etc/usb_modeswitch.d/12d1:1c0b

Paste the following:

DefaultVendor=0x12d1 
DefaultProduct=0x1c0b 
TargetVendor=0x12d1 
TargetProduct=0x1c05 
CheckSuccess=20 
MessageEndpoint=0x0f 
MessageContent="55534243123456780000000000000011062000000100000000000000000000"

Save it (Ctrl+X). At this point you can either remove your modem and re-insert it for it to be switched to modem mode automatically or use the following line to do it manually:

usb_modeswitch -c /etc/usb_modeswitch.d/12d1:1c0b

Check if the modem is switched

lsusb | grep Huawei

The output should be something like this:

Bus 003 Device 003: ID 12d1:1c05 Huawei Technologies Co., Ltd.

Note that the product ID has changed from 1c0b to 1c05. It means that the USB stick can now be used as a modem. Also note that it can take some time (probably not more than 15 seconds) for the modem to switch if you removed and re-inserted it instead of running usb_modeswitch manually.

Connecting

The easiest way to connect is with sakis3g. Install ppp (base) if not installed:

pacman -Sy ppp

Download and install sakis3g from [1]:

wget http://www.sakis3g.org/versions/latest/i386/sakis3g.gz
gunzip sakis3gz
mv sakis3g /usr/bin

Run sakis3g:

sakis3g --interactive

You'll have to provide APN, username and password, assuming everything goes right you should be connected by now.

Connect at system startup with sakis3g

First you need to create a configuration file:

nano /etc/sakis3g.conf

This is how my configuration file looks like, it'll work if you're using T-Mobile in the UK (the first line should be left as is):

USBDRIVER="option"
APN="CUSTOM_APN"
CUSTOM_APN="general.t-mobile.uk"
APN_USER="t-mobile"
APN_PASS="tm"

Save it (Ctrl+X) and now you're almost finished. What you need to do is to run sakis3g connect at system startup. For some reason putting it in /etc/rc.local doesn't work so a good option if you're using X but not using a login manager like GDM is to put it in your .xinitrc:

sudo sakis3g connect &
exec openbox

For this you first need to edit /etc/sudoers and add the following line:

username ALL=(ALL) NOPASSWD:/usr/bin/sakis3g

Replace username with your username.