USB hplip scanner - user permissions issue

djeeke · 05-06-2011, 09:17 AM

Hi all,

First thread here so I hope this is the good subforum, not really hardware related issue as the scanner works (tested as root) and not really software either... My guess it's all about permissions/groups...

I want to share an HP Photosmart C4100 series scanner connected via USB to a server box running ClearOS... (CentOS)

So far I have connected the scanner, installed hplip & sane...
Root user is able to see the scanner... and scan from it...
Sane deamon is installed and running, I can connect to it from a remote system.

Quote:

[root@local ~]# uname -a
Linux local 2.6.18-194.8.1.v5 #1 SMP Thu Jul 15 01:14:04 EDT 2010 i686 i686 i386 GNU/Linux
[root@local ~]# lsusb
Bus 001 Device 004: ID 03f0:5711 Hewlett-Packard PhotoSmart C4100 series
Bus 001 Device 001: ID 0000:0000
Bus 002 Device 001: ID 0000:0000
Bus 003 Device 001: ID 0000:0000
Bus 004 Device 001: ID 0000:0000
Bus 005 Device 001: ID 0000:0000
[root@local ~]# scanimage -L
device `hpaio:/usb/Photosmart_C4100_series?serial=MY71IH724R05J7' is a Hewlett-Packard Photosmart_C4100_series all-in-one
[root@local ~]#

My problem however is that no user apart from root detects the scanner... This Linux distribution has no groups like scanner or usb...

Quote:

djeeke@local:~$ scanimage -L

No scanners were identified. If you were expecting something different,
check that the scanner is plugged in, turned on and detected by the
sane-find-scanner tool (if appropriate). Please read the documentation
which came with this software (README, FAQ, manpages).
djeeke@local:~$

Anybody that can point me in a good direction ?

tronayne · 05-06-2011, 10:40 AM

I have a H-P Photosmart C4680, essentially the same thing you've got. The way it seems to want to work is that my user ID is included the these groups:

Code:

fgrep trona /etc/group
lp:x:7:lp,trona
floppy:x:11:root,trona
audio:x:17:root,trona
video:x:18:root,trona
cdrom:x:19:root,trona
plugdev:x:83:root,trona
power:x:84:root,trona
usbfs:x:85:root,trona,vboxusers
netdev:x:86:root,trona
scanner:x:93:root,trona
vboxusers:x:102:trona
cvs:x:103:trona

You won't care about vboxusers and cvs but you do care about lp and scanner. If you don't have a scanner group, add it with a unique GID (you can do that with vi, by the way); 93 in this case. I then use xsane to scan.

Once you've got it going, you'll have a .sane directory in your home directory:

Code:

tree .sane
.sane
`-- xsane
    |-- Hewlett-Packard:Photosmart__C4600__series.drc
    |-- batch-lists
    |-- xsane.mdf
    `-- xsane.rc

2 directories, 3 files

Hope this helps some.

djeeke · 05-19-2011, 06:19 AM

Hi !

Thanks for this info... One step closer...

My test account on the ClearOS box is added to the new 'scanner' group and I do see the scanner !

Quote:

scanner:x:93:root,saned,xinetd,djeeke

Quote:

[djeeke@local ~]$ /sbin/lsusb
Bus 001 Device 010: ID 03f0:5711 Hewlett-Packard PhotoSmart C4100 series
Bus 001 Device 001: ID 0000:0000
Bus 002 Device 001: ID 0000:0000
Bus 003 Device 001: ID 0000:0000
Bus 004 Device 001: ID 0000:0000
Bus 005 Device 001: ID 0000:0000
[djeeke@local ~]$ scanimage -L
device `hpaio:/usb/Photosmart_C4100_series?serial=MY71IH725R04J7' is a Hewlett-Packard Photosmart_C4100_series all-in-one
[djeeke@local ~]$

Next issue is the remote connection...

I have saned running, when connecting from a remote system I see the incoming connection in /var/log/messages :

Quote:

May 19 13:11:52 local xinetd[7860]: START: sane-port pid=27174 from=10.8.0.10
May 19 13:11:52 local xinetd[7860]: EXIT: sane-port status=0 pid=27174 duration=0(sec)

But I do not see the scanner : scanimage -L output from my ubuntu :

Quote:

djeeke@djeeke-laptop:~$ scanimage -L

No scanners were identified. If you were expecting something different,
check that the scanner is plugged in, turned on and detected by the
sane-find-scanner tool (if appropriate). Please read the documentation
which came with this software (README, FAQ, manpages).
djeeke@djeeke-laptop:~$

I have tried adding saned and xinetd to the scanner group as well but no luck...
I'm one step away from having this working now !

Can someone push me in the right direction ?
Thanks

djeeke · 05-19-2011, 07:10 AM

I found some information but it's above my head and I don't know if it's relevant or not ...
Could someone explain what the following file is about ?
/etc/udev/rules.d/60-libsane.rules

It does list some scanners (mine is not included)...

Same with
/etc/udev/rules.d/55-hpmud.rules

I guess I might need a udev crashcourse ;-)

Hangdog42 · 05-19-2011, 07:11 AM

I recently had something similar with my HP OfficeJet 8500. What I found was if I tried to set up the printer directly through CUPS, the scanner wasn't seen by sane/xsane. However, if I set up the printer using hp-setup, that produced the proper configuration in CUPS for the scanner to be seen.

djeeke · 05-19-2011, 07:15 AM

Additionally I tested if user saned can see the scanner :

Quote:

[root@local ~]# su -s /bin/sh - saned
-sh-3.2$ scanimage -L
device `hpaio:/usb/Photosmart_C4100_series?serial=MY71IH725R04J7' is a Hewlett-Packard Photosmart_C4100_series all-in-one
-sh-3.2$

It looks like I'm very close to the answer of the puzzle... I just need some help fitting the last pieces ;-)

djeeke · 05-19-2011, 07:19 AM

Thanks for the hint Hangdog...

I did use hp-setup to install the printer/scanner ...

This must be a permission/ownership issue, I must be overlooking something though...

djeeke · 05-19-2011, 08:26 AM

With regards to my previous questions, as I don't see the scanner in those files, can I easily change the rules and reload udev ???

djeeke · 05-25-2011, 04:40 AM

I unsuccessfully tried a few other things...

Nobody has any idea on what I'm missing here ???

Hangdog42 · 05-25-2011, 07:22 AM

What kind of URL is CUPS using to try and connect to the printer? I know it is kind of fishing, but I've never had any problems like this with a HP scanner set up by hp-setup. By the way, I can't imagine that you would have to mess with udev. I may be wrong, but it seems more like a driver-level issue to me.

H_TeXMeX_H · 05-25-2011, 07:34 AM

Make sure to be part of the 'scanner' and 'lp' groups.

djeeke · 05-26-2011, 05:49 AM

Well yes I hope I have made 'beginner' error like forgetting to power on the system ;-)
thanks for thinking with me...

CUPS does not seem to be the issue... Printing works fine... It is a sane/saned issue...

On my test ubuntu 'client' system /etc/sane.d/net.conf has 192.168.0.254 as single entry

on the 'server' /var/log/messages shows up the following at each connectivity attempt through 'telnet on port 6566' or 'scanimage -L' from the client system :

Quote:

May 26 12:09:00 local xinetd[30197]: START: sane-port pid=21879 from=10.8.0.10
May 26 12:09:00 local xinetd[30197]: EXIT: sane-port status=0 pid=21879 duration=0(sec)

on the server system, my saned.conf file allows access from three subnets:

Quote:

# saned.conf
192.168.0.0/24
192.168.1.0/24
192.168.2.0/24

Xinetd.conf has the following statements :

Quote:

service sane-port
{
port = 6566
socket_type = stream
wait = no
user = saned
group = saned
server = /usr/sbin/saned
disable = no
}

I checked and my test user djeeke and saned user are part of lp and scanner groups...
from the 'group' file :

Quote:

lp:x:7:daemon,lp,saned,xinetd,djeeke
scanner:x:93:root,saned,xinetd,djeeke

On the server users djeeke and saned see the scanner (through scanimage -L)

Only from the client system I get the dreaded "No scanners were identified" message...

Hangdog42 · 05-26-2011, 07:13 AM

Quote:

CUPS does not seem to be the issue... Printing works fine... It is a sane/saned issue...

Sorry, I should have explained my thinking a bit more. When I was having problems with my Officejet, one of the clues was that CUPS was connecting with the wrong URL. Like you, I could print but not scan. When I dug into it, I found that the setup had been goofed up, and running hp-setup was the key. Now I do realize that you have run hp-setup, but I'm trying to look for clues.

Quote:

I checked and my test user djeeke and saned user are part of lp and scanner groups...
from the 'group' file :

Are you in both groups on both the client and the server?

H_TeXMeX_H · 05-26-2011, 10:49 AM

Go:
http://localhost:631/
click printers, then your printer, and look for a 'serial=' on the connection line.

djeeke · 05-27-2011, 04:55 AM

Quote:

Originally Posted by Hangdog42

Sorry, I should have explained my thinking a bit more. When I was having problems with my Officejet, one of the clues was that CUPS was connecting with the wrong URL. Like you, I could print but not scan. When I dug into it, I found that the setup had been goofed up, and running hp-setup was the key. Now I do realize that you have run hp-setup, but I'm trying to look for clues.

No apologies Hangdog, thanks for trying to help !!! I did re-run hp-setup more than once though...
But still, what would be the link between CUPS and saned ? One would expect to be able to run saned and scan from a remote system even without CUPS (printing is another story) What would be the dependencies

Quote:

Originally Posted by Hangdog42

Are you in both groups on both the client and the server?

OK, user djeeke is in both groups on both systems I have no saned on my client system... I do not get a response even if I'm root on the client system...
Do you think I need to run a server deamon on the client ? As ultimately the client systems will be windows clients and I don't now how the windows 'sanetwain' application manages this...

Quote:

Originally Posted by H_TeXMeX_H

Go:
http://localhost:631/
click printers, then your printer, and look for a 'serial=' on the connection line.

Device URI: hp:/usb/Photosmart_C4100_series?serial=MY71IH725R04J7

Same serial number as I get from 'scanimage -L'