install modem ZTE AC2726 to linux

Insert the modem in USB interface and see if that gets detected.

$ lsusb
Bus 005 Device 002: ID 19d2:fff5

I noticed in /var/log/messsages that the device is detected as usb storage. To make it detected as modem we will use usb-modeswitch package. It is a Switching tool for controlling "flip flop" USB devices.

Download usb_switch package from here and install.
$ sudo dpkg -i usb-modeswitch_1.0.2-1_i386.deb

Unplug and plugin the modem back.

$ lsusb
Bus 005 Device 004: ID 19d2:fff1 <- add="" amp="" and="" as="" below:="" can="" change="" check="" conf="" config="" configure="" correctly="" detect="" detected="" dialer="" entries="" etc="" found="" id="" in="" is="" logs="" missing="" modem="" modprobe="" notice="" now.="" password="" phone="#777" product="0xfff1" run:="" see="" sudo="" that="" the="" to="" usbserial="" vendor="0x19d2" vi="" wvdial.conf="" wvdial="" wvdialconf="" you="">
Username =
Baud = 460800
Stupid Mode = 1
New PPPD = 1
Tonline = 0

Note: Give a valid username & password in the corresponding lines above and uncomment them (Hint: remove ";" from the beginning of the line).

$ sudo wvdial

The connection started working. Note that you can also configure gnome-ppp or kpp to connect.