I'm running raspbian stretch on a Pi 3. I used these instructions, to use it as a wifi and ethernet router with systemd-networkd while USB tethering with my phone:
How can I set my up to be WiFi AND ethernet router simultaneously?
It works well, but I'm hoping that using a dedicated wifi usb dongle, rather than the integrated chip will boost the signal range, which is currently quite limited. Thus, I plugged in an 802.11 USB 2.0 wifi dongle by TP-Link: TL-WN721N.
It is recognized and the firmware is found and transferred to the device:
root@raspberrypi:/home/pi# lsusb
Bus 001 Device 009: ID 04e8:6863 Samsung Electronics Co., Ltd GT-I9500 [Galaxy S4] / GT-I9250 [Galaxy Nexus] (network tethering)
Bus 001 Device 011: ID 0cf3:9271 Atheros Communications, Inc. AR9271 802.11n
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. SMSC9512/9514 Fast Ethernet Adapter
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp. SMC9514 Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
It isn't recognized as an interface:
root@raspberrypi:/home/pi# ifconfig
br0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet XXX netmask 255.255.255.0 broadcast XXX
inet6 XXX prefixlen 64 scopeid 0x20<link>
ether XXX txqueuelen 1000 (Ethernet)
RX packets 193945 bytes 19974390 (19.0 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 215853 bytes 204862309 (195.3 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
ether XXX txqueuelen 1000 (Ethernet)
RX packets 149329 bytes 11146560 (10.6 MiB)
RX errors 0 dropped 5 overruns 0 frame 0
TX packets 153299 bytes 121050626 (115.4 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Local Loopback)
RX packets 198 bytes 15881 (15.5 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 198 bytes 15881 (15.5 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
usb0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet XXX netmask 255.255.255.0 broadcast XXX
inet6 XXX prefixlen 64 scopeid 0x20<link>
ether XXX txqueuelen 1000 (Ethernet)
RX packets 34059 bytes 43252645 (41.2 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 17832 bytes 2613527 (2.4 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
wlan0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 XXX prefixlen 64 scopeid 0x20<link>
ether XXX txqueuelen 1000 (Ethernet)
RX packets 56321 bytes 9517115 (9.0 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 68291 bytes 87965290 (83.8 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
dmesg:
[ 1670.073838] usb 1-1.3: new high-speed USB device number 11 using dwc_otg
[ 1670.224647] usb 1-1.3: New USB device found, idVendor=0cf3, idProduct=9271, bcdDevice= 1.08
[ 1670.224658] usb 1-1.3: New USB device strings: Mfr=16, Product=32, SerialNumber=48
[ 1670.224663] usb 1-1.3: Product: USB2.0 WLAN
[ 1670.224669] usb 1-1.3: Manufacturer: ATHEROS
[ 1670.224674] usb 1-1.3: SerialNumber: 12345
[ 1670.225308] usb 1-1.3: ath9k_htc: Firmware ath9k_htc/htc_9271-1.4.0.fw requested
[ 1670.516779] usb 1-1.3: ath9k_htc: Transferred FW: ath9k_htc/htc_9271-1.4.0.fw, size: 51008
[ 1670.776458] ath9k_htc 1-1.3:1.0: ath9k_htc: HTC initialized with 33 credits
[ 1671.209588] ath9k_htc 1-1.3:1.0: ath9k_htc: FW Version: 1.4
[ 1671.209597] ath9k_htc 1-1.3:1.0: FW RMW support: On
[ 1671.209603] ath: EEPROM regdomain: 0x809c
[ 1671.209606] ath: EEPROM indicates we should expect a country code
[ 1671.209609] ath: doing EEPROM country->regdmn map search
[ 1671.209613] ath: country maps to regdmn code: 0x52
[ 1671.209617] ath: Country alpha2 being used: CN
[ 1671.209620] ath: Regpair used: 0x52
[ 1671.221842] ieee80211 phy6: Atheros AR9271 Rev:1
What do I need to do register this dongle as an interface?
