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*SOLVED* No parallel port on VE [message #7525]

Tue, 17 October 2006 03:42

ferp2
Messages: 29
Registered: May 2006

Junior Member

Hello,

After installing CUPS on a VE, I discovered I could not connect to my printer because there is no available parallel port. Meanwhile, I can access the printer via the parallel port on the HN. How would I access the parallel port on the VE.

Thanks

[Updated on: Thu, 19 October 2006 13:50] by Moderator

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Re: No parallel port on VE [message #7529 is a reply to message #7525]

Tue, 17 October 2006 07:13

Vasily Tarasov
Messages: 1345
Registered: January 2006

Senior Member

You should add parallel port device to VE using set <veid> --devnodes command of vzctl.

HTH,
vass.

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Re: No parallel port on VE [message #7593 is a reply to message #7529]

Wed, 18 October 2006 13:38

ferp2
Messages: 29
Registered: May 2006

Junior Member

Hi Vass,

I've followed your recommendation:

Quote:

You should add parallel port device to VE using set <veid> --devnodes command of vzctl.

But lp0 remains inaccessible to the VE. Only when I start the cups server in the HN can I start to access lp0 in the VE.

I have also tried the following without success:

1. Manually re-added lp0 to the VE using the vzctl set <veid> --devnodes lp0:rw command.

2. Restarted the VE.

3. Restarted cups server in the VE.

4. Entered vzctl set <veid> --devnodes lp0:rw --save and restarted the HN.

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Re: No parallel port on VE [message #7616 is a reply to message #7593]

Thu, 19 October 2006 08:08

dev
Messages: 1693
Registered: September 2005
Location: Moscow

Senior Member

Quote:

But lp0 remains inaccessible to the VE.

what do you mean by that? how is it inaccessible?
what are the exact messages on the screen/logs etc.?
what are the commands you are trying to execute and fail?

please, provide detailed questions if you want real feedback on the issues.

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Re: No parallel port on VE [message #7649 is a reply to message #7616]

Thu, 19 October 2006 13:19

ferp2
Messages: 29
Registered: May 2006

Junior Member

Quote:

what do you mean by that? how is it inaccessible?
what are the exact messages on the screen/logs etc.?
what are the commands you are trying to execute and fail?

After doing vzctl set <veid> --devnodes lp0:rw, there is still no /dev/lp0 device in the VE. As a result I cannot print from the VE. When I set up the printer in CUPS, I cannot set the device URI to the parallel port because there is no parallel port. Here's what happens when I try to print directly to the device:

Quote:

echo "sdfsdf" > /dev/lp0
bash: /dev/lp0: No such device or address

I have found a temporary solution to this problem as follows:
To be able to print to the /dev/lp0 device in the VE, I have to start the cups daemon in the HN. I have to do this every time I reboot the HN server.

Please note that I have already done vzctl set <veid> --devnodes lp0:rw --save.

Thank you.

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Re: No parallel port on VE [message #7650 is a reply to message #7649]

Thu, 19 October 2006 13:22

dev
Messages: 1693
Registered: September 2005
Location: Moscow

Senior Member

can you check the following:
1. ls -la /dev/lp* in VE, when it doesn't work.

2. check modules loaded in VE0 after reboot with lsmod and after cupsd startup. I guess there are some kernel modules which should be loaded and surely this can not be done from VE.

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Re: No parallel port on VE [message #7652 is a reply to message #7650]

Thu, 19 October 2006 13:46

ferp2
Messages: 29
Registered: May 2006

Junior Member

Quote:

1. ls -la /dev/lp* in VE, when it doesn't work.

ls -la /dev/lp*
crw-r----- 1 root root 6, 0 Oct 17 09:50 /dev/lp0
crw-r----- 1 root root 6, 1 Oct 17 17:17 /dev/lp1
crw-r----- 1 root root 6, 2 Oct 17 17:19 /dev/lp2

Quote:

check modules loaded in VE0 after reboot with lsmod and after cupsd startup. I guess there are some kernel modules which should be loaded and surely this can not be done from VE.

On HN (VE0):
Before starting cupsd:
lsmod | grep parport

After starting cupsd:
lsmod | grep parport
parport_pc 19776 1
parport 20992 2 parport_pc,lp

It looks like starting cupsd in VE0 modprobes parallel port modules, whereas this is not the case when starting cupsd in VEx.

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Re: No parallel port on VE [message #7654 is a reply to message #7652]

Thu, 19 October 2006 13:57

dev
Messages: 1693
Registered: September 2005
Location: Moscow

Senior Member

exactly. modules can be loaded by administrator request only.
just load these modules in your rc.local scripts on node boot up or on VE start or ... as you like Smile