On Friday, January 8, 2021, 07:07:40 PM EST, Brian <ad44@cityscape.co.uk> wrote:
On Fri 08 Jan 2021 at 17:28:16 -0500, Jen Nussbaum wrote:
>> When I run simple-scan, it detects the printer and announces itself
>> ready to go, but when I try to scan anything, I get the message
>> "Failed to scan Unable to connect to scanner". I Googled for anything
>> related to this; there's a bunch of stuff on Ubuntu and Mint forums
>> about purging the "ippusbxd" package, but this isn't on Debian.
>
> ippusbxd is certainly not on Debian but ipp-usb is. See the wiki.
Yes, and I do have that; the point was just that the solution that worked on
Mint (to remove ippusbxd and install ipp-usb) isn't relevant here.
>> I then ran simple-scan with the debug flag, and at the moment I try to
>> initiate a scan, I got:
>>
>> [+20.83s] DEBUG: simple-scan.vala:1817: Requesting scan at 150 dpi from device 'escl:
http://127.0.0.1:60000'>> [+20.83s] DEBUG: scanner.vala:1683: Scanner.scan ("escl:
http://127.0.0.1:60000", dpi=150, scan_mode=ScanMode.GRAY, depth=2, type=single, paper_width=0, paper_height=0, brightness=0, contrast=0, delay=3000ms)
>> [+20.83s] DEBUG: scanner.vala:828: Processing request
>> [+20.83s] DEBUG: scanner.vala:889: sane_open ("escl:
http://127.0.0.1:60000") -> SANE_STATUS_NO_MEM
>> [+20.83s] WARNING: scanner.vala:893: Unable to open device: Out of memory
>
> Nothing about the pixma backend (driver)?
pixma only appears during the startup:
[+7.62s] DEBUG: scanner.vala:353: Device: name="pixma:04A91913_47A8A4" vendor="CANON" model="CanoScan LiDE 300" type="multi-function peripheral"> Just to confirm your experience, what happens with scanning with
>
> simple-scan "pixma:04A91913_47A8A4"
This fires up simple scan, and when I click on "scan" it scans the document successfully.
> and
>
> simple-scan "escl:
http://127.0.0.1:60000"
This does _not_ work; the response here is the same as when I run it normally, i.e. the "Unable to contact scanner" error.
>> I don't know why I tried this, but I then ran simple-scan as root,
>> and...it worked perfectly.
>
> I do not understand why this should be so. Do both the previous commands
> work as root?
The "pixma" version worked as root, as it did as the regular user. Curiously, the "escl" version did not work as root,
even though when I run simple-scan without any arguments, it did work as root.
> > I'm bewildered by this--any idea what I should be looking at?
>
> Yes; there is a possible solution. Give what you get for
>
> lsusb -v | grep -A 3 bInterfaceClass.*7
---
$ lsusb -v | grep -A 3 bInterfaceClass.*7
Couldn't open device, some information will be missing
bInterfaceClass 7 Printer
bInterfaceSubClass 1 Printer
bInterfaceProtocol 4
iInterface 0
can't get debug descriptor: Resource temporarily unavailable
Couldn't open device, some information will be missing
Couldn't open device, some information will be missing
--
bInterfaceClass 7 Printer
bInterfaceSubClass 1 Printer
bInterfaceProtocol 4
iInterface 0
Couldn't open device, some information will be missing
Couldn't open device, some information will be missing
can't get debug descriptor: Resource temporarily unavailable
Couldn't open device, some information will be missing
---
(The "Couldn't open device" line was repeated multiple times wherever it appeared;
I deleted it here for brevity.)
> and
>
> systemctl list-units "ipp-usb*" | grep service
---
$ systemctl list-units "ipp-usb*" | grep service
ipp-usb.service loaded active running Daemon for IPP over USB printer support
---
Thank you.