I've made a bit of progress with this, following your link above, Philip, and going to the Command Line instructions.
Just to recap, this is what I've done.
Command ip a gave:
[...]
[...]
3: wlp3s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN group default qlen 1000
link/ether b8:ee:65:58:79:89 brd ff:ff:ff:ff:ff:ff
inet6 fe80::baee:65ff:fe58:7989/64 scope link
valid_lft forever preferred_lft forever
Command iw dev gave:
phy#0
Interface wlp3s0
ifindex 3
wdev 0x1
addr b8:ee:65:58:79:89
type managed
txpower 200.00 dBm
Command ip link set wlp3s0 up gave:
No response or error code.
Command iwlist scan gave:
wlp3s0 Scan completed :
[...]
Cell 12 - Address: EC:08:6B:94:41:10
Channel:13
Frequency:2.472 GHz (Channel 13)
Quality=52/70 Signal level=-58 dBm
Encryption key:on
ESSID:"TP-LINK_4110"
Bit Rates:9 Mb/s; 18 Mb/s; 36 Mb/s; 54 Mb/s; 1 Mb/s
2 Mb/s; 5.5 Mb/s; 11 Mb/s
Bit Rates:6 Mb/s; 12 Mb/s; 24 Mb/s; 48 Mb/s
Mode:Master
Extra:tsf=0000000000000000
Extra: Last beacon: 8ms ago
IE: Unknown: (numbers here, followed by lots of similar lines)
I edited /etc/network/interfaces, and added:
allow-hotplug wlp3s0
iface wlp3s0 inet dhcp
wpa-ssid TP-LINK_4110
wpa-psk [My network password here]
* Not sure if TP-LINK_4110 should be in double quotes, or single quotes or none. Instructions don't say.
* For wpa-psk, I put in my normal password for the network, not a long key specially produced by the wpa_passphrase (as described later in the instructions)
Next, command ifup wlp3s0 gave:
wpa_supplicant: /sbin/wpa_supplicant daemon failed to start
run-parts: /etc/network/if-pre-up.d/wpasupplicant exited with return code 1
ifup: failed to bring up wlp3s0
Obviously, the command iw wlp3s0 link gave:
Not connected.
And a repeat of command ip a gave:
[...]
[...]
3: wlp3s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN group default qlen 1000
link/ether b8:ee:65:58:79:89 brd ff:ff:ff:ff:ff:ff
inet6 fe80::baee:65ff:fe58:7989/64 scope link
valid_lft forever preferred_lft forever
Next, I checked that wpa_supplicant was installed:
wpasupplicant is already the newest version (2:2.7+git20190128+0c1e29f-6+deb10u2).
Next I tried to find wpa_supplicant.conf. This was not at /etc/wpa_supplicant/wpa_supplicant.conf. However, I found it at /etc/dbus-1/system.d/wpa_supplicant.conf
Then, I used wpa_passphrase to calculate the correct WPA PSK hash for my SSID, and followed instructions to add this to wpa_supplicant.conf (edited result here!):
<!DOCTYPE busconfig PUBLIC
"-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN"
"http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">
<busconfig>
<policy user="root">
<allow own="fi.epitest.hostap.WPASupplicant"/>
<allow send_destination="fi.epitest.hostap.WPASupplicant"/>
<allow send_interface="fi.epitest.hostap.WPASupplicant"/>
<allow own="fi.w1.wpa_supplicant1"/>
<allow send_destination="fi.w1.wpa_supplicant1"/>
<allow send_interface="fi.w1.wpa_supplicant1"/>
<allow receive_sender="fi.w1.wpa_supplicant1" receive_type="signal"/>
</policy>
<policy group="netdev">
<allow send_destination="fi.epitest.hostap.WPASupplicant"/>
<allow send_interface="fi.epitest.hostap.WPASupplicant"/>
<allow send_destination="fi.w1.wpa_supplicant1"/>
<allow send_interface="fi.w1.wpa_supplicant1"/>
<allow receive_sender="fi.w1.wpa_supplicant1" receive_type="signal"/>
</policy>
<policy context="default">
<deny own="fi.epitest.hostap.WPASupplicant"/>
<deny send_destination="fi.epitest.hostap.WPASupplicant"/>
<deny own="fi.w1.wpa_supplicant1"/>
<deny send_destination="fi.w1.wpa_supplicant1"/>
<deny receive_sender="fi.w1.wpa_supplicant1" receive_type="signal"/>
</policy>
</busconfig>
network={
ssid="TP-LINK_4110"
#psk="XXXXXXXX"
psk=XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
}
ctrl_interface=/run/wpa_supplicant
update_config=1
The next command in the instructions was systemctl reenable wpa_supplicant.service, which gave:
Removed /etc/systemd/system/dbus-fi.w1.wpa_supplicant1.service.
Removed /etc/systemd/system/multi-user.target.wants/wpa_supplicant.service.
Created symlink /etc/systemd/system/dbus-fi.w1.wpa_supplicant1.service → /lib/systemd/system/wpa_supplicant.service.
Created symlink /etc/systemd/system/multi-user.target.wants/wpa_supplicant.service → /lib/systemd/system/wpa_supplicant.service.
Then, systemctl restart wpa_supplicant.service gave:
Job for wpa_supplicant.service failed because the control process exited with error code.
See "systemctl status wpa_supplicant.service" and "journalctl -xe" for details.
I followed the advice given in the command feedback, and did systemctl status wpa_supplicant.service:
root@newdelldebian:~# systemctl status wpa_supplicant.service
● wpa_supplicant.service - WPA supplicant
Loaded: loaded (/lib/systemd/system/wpa_supplicant.service; enabled; vendor preset: enabled)
Active: failed (Result: exit-code) since Thu 2021-01-07 11:11:09 GMT; 42s ago
Process: 4558 ExecStart=/sbin/wpa_supplicant -u -s -O /run/wpa_supplicant (code=exited, status=255/EXCEPTION)
Main PID: 4558 (code=exited, status=255/EXCEPTION)
Jan 07 11:11:09 newdelldebian systemd[1]: Starting WPA supplicant...
Jan 07 11:11:09 newdelldebian wpa_supplicant[4558]: dbus: Could not request service name: org.freedesktop.DBus.Error.AccessDenied Connection ":1.646" is not allowed to own the service "fi.w1
Jan 07 11:11:09 newdelldebian wpa_supplicant[4558]: Failed to initialize wpa_supplicant
Jan 07 11:11:09 newdelldebian systemd[1]: wpa_supplicant.service: Main process exited, code=exited, status=255/EXCEPTION
Jan 07 11:11:09 newdelldebian systemd[1]: wpa_supplicant.service: Failed with result 'exit-code'.
Jan 07 11:11:09 newdelldebian systemd[1]: Failed to start WPA supplicant.
That's as far as I've got for now. I'm not really sure what I'm doing, but I'm attempting to follow the instructions accurately.
Got to do some work now, so will return to this later.
Thanks for the help so far.