Can no longer print using CUPS

Question

I have a Brother_HL_L3270CDW_series printer which worked out-of-the-box, was detected by Ubuntu 22.04 over WiFi and could print immediately.

It stopped working and I don't know why. With cupsctl --debug-logging, here are is /var/log/cups/error_log when the printer has been removed using Ubuntu settings app (apologies for the masses of repetitions -- a short, filtered version is at the bottom):

D [29/Oct/2022:11:38:06 +0100] cupsdSetBusyState: newbusy="Active clients", busy="Not busy"
D [29/Oct/2022:11:38:06 +0100] [Client 69] Server address is "/run/cups/cups.sock".
D [29/Oct/2022:11:38:06 +0100] [Client 69] Accepted from localhost (Domain)
D [29/Oct/2022:11:38:06 +0100] [Client 69] Waiting for request.
I [29/Oct/2022:11:38:06 +0100] Expiring subscriptions...
D [29/Oct/2022:11:38:06 +0100] [Client 69] POST / HTTP/1.1
D [29/Oct/2022:11:38:06 +0100] cupsdSetBusyState: newbusy="Active clients", busy="Active clients"
D [29/Oct/2022:11:38:06 +0100] [Client 69] Read: status=200, state=6
D [29/Oct/2022:11:38:06 +0100] [Client 69] No authentication data provided.
D [29/Oct/2022:11:38:06 +0100] [Client 69] 2.0 Get-Printer-Attributes 1
D [29/Oct/2022:11:38:06 +0100] Get-Printer-Attributes ipp://localhost/printers/Brother_HL_L3270CDW_series
D [29/Oct/2022:11:38:06 +0100] Get-Printer-Attributes client-error-not-found: The printer or class does not exist.
D [29/Oct/2022:11:38:06 +0100] [Client 69] Returning IPP client-error-not-found for Get-Printer-Attributes (ipp://localhost/printers/Brother_HL_L3270CDW_series) from localhost.
D [29/Oct/2022:11:38:06 +0100] [Client 69] Content-Length: 130
D [29/Oct/2022:11:38:06 +0100] [Client 69] cupsdSendHeader: code=200, type="application/ipp", auth_type=0
D [29/Oct/2022:11:38:06 +0100] [Client 69] con->http=0x5607c3896200
D [29/Oct/2022:11:38:06 +0100] [Client 69] cupsdWriteClient error=0, used=0, state=HTTP_STATE_POST_SEND, data_encoding=HTTP_ENCODING_LENGTH, data_remaining=130, response=0x5607c391ffe0(IPP_STATE_DATA), pipe_pid=0, file=-1
D [29/Oct/2022:11:38:06 +0100] [Client 69] Writing IPP response, ipp_state=IPP_STATE_DATA, old wused=0, new wused=0
D [29/Oct/2022:11:38:06 +0100] [Client 69] bytes=0, http_state=0, data_remaining=130
D [29/Oct/2022:11:38:06 +0100] [Client 69] Flushing write buffer.
D [29/Oct/2022:11:38:06 +0100] [Client 69] New state is HTTP_STATE_WAITING
D [29/Oct/2022:11:38:06 +0100] [Client 69] Waiting for request.
D [29/Oct/2022:11:38:06 +0100] cupsdSetBusyState: newbusy="Not busy", busy="Active clients"
D [29/Oct/2022:11:38:06 +0100] [Client 69] POST /admin/ HTTP/1.1
D [29/Oct/2022:11:38:06 +0100] cupsdSetBusyState: newbusy="Active clients", busy="Not busy"
D [29/Oct/2022:11:38:06 +0100] [Client 69] Read: status=200, state=6
D [29/Oct/2022:11:38:06 +0100] [Client 69] No authentication data provided.
D [29/Oct/2022:11:38:06 +0100] [Client 69] 2.0 CUPS-Delete-Printer 2
D [29/Oct/2022:11:38:06 +0100] CUPS-Delete-Printer ipp://localhost/printers/Brother_HL_L3270CDW_series
D [29/Oct/2022:11:38:06 +0100] CUPS-Delete-Printer client-error-not-found: The printer or class does not exist.
D [29/Oct/2022:11:38:06 +0100] [Client 69] Returning IPP client-error-not-found for CUPS-Delete-Printer (ipp://localhost/printers/Brother_HL_L3270CDW_series) from localhost.
D [29/Oct/2022:11:38:06 +0100] [Client 69] Content-Length: 130
D [29/Oct/2022:11:38:06 +0100] [Client 69] cupsdSendHeader: code=200, type="application/ipp", auth_type=0
D [29/Oct/2022:11:38:06 +0100] [Client 69] con->http=0x5607c3896200
D [29/Oct/2022:11:38:06 +0100] [Client 69] cupsdWriteClient error=0, used=0, state=HTTP_STATE_POST_SEND, data_encoding=HTTP_ENCODING_LENGTH, data_remaining=130, response=0x5607c391fd20(IPP_STATE_DATA), pipe_pid=0, file=-1
D [29/Oct/2022:11:38:06 +0100] [Client 69] Writing IPP response, ipp_state=IPP_STATE_DATA, old wused=0, new wused=0
D [29/Oct/2022:11:38:06 +0100] [Client 69] bytes=0, http_state=0, data_remaining=130
D [29/Oct/2022:11:38:06 +0100] [Client 69] Flushing write buffer.
D [29/Oct/2022:11:38:06 +0100] [Client 69] New state is HTTP_STATE_WAITING
D [29/Oct/2022:11:38:06 +0100] [Client 69] Waiting for request.
D [29/Oct/2022:11:38:06 +0100] cupsdSetBusyState: newbusy="Not busy", busy="Active clients"
I [29/Oct/2022:11:38:07 +0100] Expiring subscriptions...
D [29/Oct/2022:11:38:37 +0100] [Client 69] HTTP_STATE_WAITING Closing for error 32 (Broken pipe)
D [29/Oct/2022:11:38:37 +0100] [Client 69] Closing connection.
D [29/Oct/2022:11:38:37 +0100] cupsdSetBusyState: newbusy="Not busy", busy="Not busy"
I [29/Oct/2022:11:38:37 +0100] Expiring subscriptions...
D [29/Oct/2022:11:38:37 +0100] Report: clients=3
D [29/Oct/2022:11:38:37 +0100] Report: jobs=0
D [29/Oct/2022:11:38:37 +0100] Report: jobs-active=0
D [29/Oct/2022:11:38:37 +0100] Report: printers=0
D [29/Oct/2022:11:38:37 +0100] Report: stringpool-string-count=366
D [29/Oct/2022:11:38:37 +0100] Report: stringpool-alloc-bytes=6144
D [29/Oct/2022:11:38:37 +0100] Report: stringpool-total-bytes=6336
I [29/Oct/2022:11:38:38 +0100] Expiring subscriptions...

I hit "Add Printer" and it is found, but fails to download drivers

Log is too big to paste directly, so:

• https://pastebin.com/7urbyVvd
• https://pastebin.com/LJL6fCfQ
• https://pastebin.com/eJ49fV7q

The "Add Printer" button becomes grey, so I close the Settings app

D [29/Oct/2022:11:39:47 +0100] [Client 70] HTTP_STATE_WAITING Closing for error 32 (Broken pipe)
D [29/Oct/2022:11:39:47 +0100] [Client 70] Closing connection.
D [29/Oct/2022:11:39:47 +0100] cupsdSetBusyState: newbusy="Dirty files", busy="Dirty files"
I [29/Oct/2022:11:39:47 +0100] Expiring subscriptions...
D [29/Oct/2022:11:39:47 +0100] Report: clients=6
D [29/Oct/2022:11:39:47 +0100] Report: jobs=0
D [29/Oct/2022:11:39:47 +0100] Report: jobs-active=0
D [29/Oct/2022:11:39:47 +0100] Report: printers=0
D [29/Oct/2022:11:39:47 +0100] Report: stringpool-string-count=366
D [29/Oct/2022:11:39:47 +0100] Report: stringpool-alloc-bytes=6144
D [29/Oct/2022:11:39:47 +0100] Report: stringpool-total-bytes=6336
I [29/Oct/2022:11:39:48 +0100] Expiring subscriptions...
D [29/Oct/2022:11:39:48 +0100] cupsdSetBusyState: newbusy="Active clients and dirty files", busy="Dirty files"
D [29/Oct/2022:11:39:48 +0100] [Client 78] Server address is "/run/cups/cups.sock".
D [29/Oct/2022:11:39:48 +0100] [Client 78] Accepted from localhost (Domain)
D [29/Oct/2022:11:39:48 +0100] [Client 78] Waiting for request.
D [29/Oct/2022:11:39:48 +0100] [Client 78] POST / HTTP/1.1
D [29/Oct/2022:11:39:48 +0100] cupsdSetBusyState: newbusy="Active clients and dirty files", busy="Active clients and dirty files"
D [29/Oct/2022:11:39:48 +0100] [Client 78] Read: status=200, state=6
D [29/Oct/2022:11:39:48 +0100] [Client 78] No authentication data provided.
D [29/Oct/2022:11:39:48 +0100] [Client 78] 2.0 Cancel-Subscription 21
D [29/Oct/2022:11:39:48 +0100] Cancel-Subscription /
D [29/Oct/2022:11:39:48 +0100] cupsdIsAuthorized: requesting-user-name="bernie"
D [29/Oct/2022:11:39:48 +0100] cupsdMarkDirty(----S)
D [29/Oct/2022:11:39:48 +0100] cupsdSetBusyState: newbusy="Active clients and dirty files", busy="Active clients and dirty files"
D [29/Oct/2022:11:39:48 +0100] [Client 78] Returning IPP successful-ok for Cancel-Subscription (/) from localhost.
D [29/Oct/2022:11:39:48 +0100] [Client 78] Content-Length: 75
D [29/Oct/2022:11:39:48 +0100] [Client 78] cupsdSendHeader: code=200, type="application/ipp", auth_type=0
D [29/Oct/2022:11:39:48 +0100] [Client 78] con->http=0x5607c3896200
D [29/Oct/2022:11:39:48 +0100] [Client 78] cupsdWriteClient error=0, used=0, state=HTTP_STATE_POST_SEND, data_encoding=HTTP_ENCODING_LENGTH, data_remaining=75, response=0x5607c389f3f0(IPP_STATE_DATA), pipe_pid=0, file=-1
D [29/Oct/2022:11:39:48 +0100] [Client 78] Writing IPP response, ipp_state=IPP_STATE_DATA, old wused=0, new wused=0
D [29/Oct/2022:11:39:48 +0100] [Client 78] bytes=0, http_state=0, data_remaining=75
D [29/Oct/2022:11:39:48 +0100] [Client 78] Flushing write buffer.
D [29/Oct/2022:11:39:48 +0100] [Client 78] New state is HTTP_STATE_WAITING
D [29/Oct/2022:11:39:48 +0100] [Client 78] Waiting for request.
D [29/Oct/2022:11:39:48 +0100] cupsdSetBusyState: newbusy="Dirty files", busy="Active clients and dirty files"
D [29/Oct/2022:11:39:48 +0100] [Client 78] POST / HTTP/1.1
D [29/Oct/2022:11:39:48 +0100] cupsdSetBusyState: newbusy="Active clients and dirty files", busy="Dirty files"
D [29/Oct/2022:11:39:48 +0100] [Client 78] Read: status=200, state=6
D [29/Oct/2022:11:39:48 +0100] [Client 78] No authentication data provided.
D [29/Oct/2022:11:39:48 +0100] [Client 78] 2.0 Cancel-Subscription 22
D [29/Oct/2022:11:39:48 +0100] Cancel-Subscription /
D [29/Oct/2022:11:39:48 +0100] Cancel-Subscription client-error-not-found: Subscription #0 does not exist.
D [29/Oct/2022:11:39:48 +0100] [Client 78] Returning IPP client-error-not-found for Cancel-Subscription (/) from localhost.
D [29/Oct/2022:11:39:48 +0100] [Client 78] Content-Length: 125
D [29/Oct/2022:11:39:48 +0100] [Client 78] cupsdSendHeader: code=200, type="application/ipp", auth_type=0
D [29/Oct/2022:11:39:48 +0100] [Client 78] con->http=0x5607c3896200
D [29/Oct/2022:11:39:48 +0100] [Client 78] cupsdWriteClient error=0, used=0, state=HTTP_STATE_POST_SEND, data_encoding=HTTP_ENCODING_LENGTH, data_remaining=125, response=0x5607c388ee70(IPP_STATE_DATA), pipe_pid=0, file=-1
D [29/Oct/2022:11:39:48 +0100] [Client 78] Writing IPP response, ipp_state=IPP_STATE_DATA, old wused=0, new wused=0
D [29/Oct/2022:11:39:48 +0100] [Client 78] bytes=0, http_state=0, data_remaining=125
D [29/Oct/2022:11:39:48 +0100] [Client 78] Flushing write buffer.
D [29/Oct/2022:11:39:48 +0100] [Client 78] New state is HTTP_STATE_WAITING
D [29/Oct/2022:11:39:48 +0100] [Client 78] Waiting for request.
D [29/Oct/2022:11:39:48 +0100] cupsdSetBusyState: newbusy="Dirty files", busy="Active clients and dirty files"
D [29/Oct/2022:11:39:48 +0100] [Client 78] HTTP_STATE_WAITING Closing for error 32 (Broken pipe)
D [29/Oct/2022:11:39:48 +0100] [Client 78] Closing connection.
D [29/Oct/2022:11:39:48 +0100] cupsdSetBusyState: newbusy="Dirty files", busy="Dirty files"
I [29/Oct/2022:11:39:49 +0100] Expiring subscriptions...
D [29/Oct/2022:11:39:57 +0100] [Client 74] HTTP_STATE_WAITING Closing for error 32 (Broken pipe)
D [29/Oct/2022:11:39:57 +0100] [Client 74] Closing connection.
D [29/Oct/2022:11:39:57 +0100] cupsdSetBusyState: newbusy="Dirty files", busy="Dirty files"
I [29/Oct/2022:11:39:57 +0100] Expiring subscriptions...
D [29/Oct/2022:11:39:57 +0100] [Client 76] HTTP_STATE_WAITING Closing for error 32 (Broken pipe)
D [29/Oct/2022:11:39:57 +0100] [Client 76] Closing connection.
D [29/Oct/2022:11:39:57 +0100] cupsdSetBusyState: newbusy="Dirty files", busy="Dirty files"
D [29/Oct/2022:11:39:57 +0100] [Client 75] HTTP_STATE_WAITING Closing for error 32 (Broken pipe)
D [29/Oct/2022:11:39:57 +0100] [Client 75] Closing connection.
D [29/Oct/2022:11:39:57 +0100] cupsdSetBusyState: newbusy="Dirty files", busy="Dirty files"
I [29/Oct/2022:11:39:58 +0100] Expiring subscriptions...

I re-open the Settings app and find that the printer has been added

• https://pastebin.com/3RajWRYG
• https://pastebin.com/7iVs8i8h
• https://pastebin.com/awNYp6LG

I try to print

• https://pastebin.com/iTA6FSMA

After about a minute, the app (libreoffice) reports that the print job failed

D [29/Oct/2022:11:41:22 +0100] [Client 103] POST / HTTP/1.1
D [29/Oct/2022:11:41:22 +0100] cupsdSetBusyState: newbusy="Active clients and dirty files", busy="Dirty files"
D [29/Oct/2022:11:41:22 +0100] [Client 103] Read: status=200, state=6
D [29/Oct/2022:11:41:22 +0100] [Client 103] No authentication data provided.
D [29/Oct/2022:11:41:22 +0100] [Client 103] 2.0 Get-Printer-Attributes 131
D [29/Oct/2022:11:41:22 +0100] Get-Printer-Attributes ipp://localhost/printers/Brother_HL_L3270CDW_series
D [29/Oct/2022:11:41:22 +0100] [Client 103] Returning IPP successful-ok for Get-Printer-Attributes (ipp://localhost/printers/Brother_HL_L3270CDW_series) from localhost.
D [29/Oct/2022:11:41:22 +0100] [Client 103] Content-Length: 98
D [29/Oct/2022:11:41:22 +0100] [Client 103] cupsdSendHeader: code=200, type="application/ipp", auth_type=0
I [29/Oct/2022:11:41:22 +0100] Expiring subscriptions...

then what looks like lots of repeats of this

D [29/Oct/2022:11:41:22 +0100] [Client 103] con->http=0x5607c3896200
D [29/Oct/2022:11:41:22 +0100] [Client 103] cupsdWriteClient error=0, used=0, state=HTTP_STATE_POST_SEND, data_encoding=HTTP_ENCODING_LENGTH, data_remaining=98, response=0x5607c388f240(IPP_STATE_DATA), pipe_pid=0, file=-1
D [29/Oct/2022:11:41:22 +0100] [Client 103] Writing IPP response, ipp_state=IPP_STATE_DATA, old wused=0, new wused=0
D [29/Oct/2022:11:41:22 +0100] [Client 103] bytes=0, http_state=0, data_remaining=98
D [29/Oct/2022:11:41:22 +0100] [Client 103] Flushing write buffer.
D [29/Oct/2022:11:41:22 +0100] [Client 103] New state is HTTP_STATE_WAITING
D [29/Oct/2022:11:41:22 +0100] [Client 103] Waiting for request.
D [29/Oct/2022:11:41:22 +0100] cupsdSetBusyState: newbusy="Dirty files", busy="Active clients and dirty files"
D [29/Oct/2022:11:41:23 +0100] [Client 103] POST / HTTP/1.1
D [29/Oct/2022:11:41:23 +0100] cupsdSetBusyState: newbusy="Active clients and dirty files", busy="Dirty files"
D [29/Oct/2022:11:41:23 +0100] [Client 103] Read: status=200, state=6
D [29/Oct/2022:11:41:23 +0100] [Client 103] No authentication data provided.
D [29/Oct/2022:11:41:23 +0100] [Client 103] 2.0 Get-Printer-Attributes 132
D [29/Oct/2022:11:41:23 +0100] Get-Printer-Attributes ipp://localhost/printers/Brother_HL_L3270CDW_series
D [29/Oct/2022:11:41:23 +0100] [Client 103] Returning IPP successful-ok for Get-Printer-Attributes (ipp://localhost/printers/Brother_HL_L3270CDW_series) from localhost.
D [29/Oct/2022:11:41:23 +0100] [Client 103] Content-Length: 98
D [29/Oct/2022:11:41:23 +0100] [Client 103] cupsdSendHeader: code=200, type="application/ipp", auth_type=0
I [29/Oct/2022:11:41:23 +0100] Expiring subscriptions...

then

• https://pastebin.com/X7uqPi8J

Does this log explain what the problem is?

I have cut and grepped those logs to extract what might be the more meaningful lines, in no particular order:

CUPS-Get-Classes client-error-not-found: No destinations added.
CUPS-Get-Default client-error-not-found: No default printer.
CUPS-Get-Printers client-error-not-found: No destinations added.
Get-Jobs client-error-not-found: The printer or class does not exist.
Get-Printer-Attributes client-error-not-found: The printer or class does not exist.
[Client 99] HTTP_STATE_WAITING Closing for error 32 (Broken pipe)
[Client 99] Returning IPP client-error-not-found for Get-Printer-Attributes (ipp://localhost/printers/Brother_HL_L3270CDW_series) from localhost.
CUPS-Add-Modify-Printer server-error-internal-error: cups-driverd failed to get PPD file - see error_log for details.
CUPS-Delete-Printer client-error-not-found: The printer or class does not exist.
[Client 83] Returning IPP client-error-not-found for Get-Jobs (ipp://localhost/printers/Brother_HL_L3270CDW_series) from localhost.
[Client 84] HTTP_STATE_WAITING Closing for error 32 (Broken pipe)
[Client 78] Returning IPP client-error-not-found for Cancel-Subscription (/) from localhost.
[Client 79] HTTP_STATE_WAITING Closing for error 32 (Broken pipe)
[Client 79] Returning IPP client-error-not-found for CUPS-Get-Default (no URI) from localhost.
[Client 79] Returning IPP client-error-not-found for CUPS-Get-Printers (no URI) from localhost.
[Client 79] Returning IPP client-error-not-found for Get-Jobs (ipp://localhost/printers/Brother_HL_L3270CDW_series) from localhost.
Cancel-Subscription client-error-not-found: Subscription #0 does not exist.

Questions I'm curious about but maybe can't get answered:

• Why does the printer fail to download drivers?
• Why does the printer get added after failing to download drivers?
• Why does printing fail if the printer was added?

Main questions:

Can I fix this incrementally, e.g. by downloading suitable drivers?

Or, since this worked at first, then something changed, is there a way to purge all printer settings so that the system is in the state that it would be after a fresh full install of Ubuntu?