Re: forcing a pci nic to use a different irq?
Sorry, I'm joining this conversation a little late so forgive
me if this has already been said...
Is your ethernet card an ISA one?
If so there should be an configuration application
that will let you move it to a different irq.
Otherwise in your BIOS somewhere there should be a setting
to assign irqs to individual PCI slots from which you
can give each slot it's own irq. The card in that slot
will use that irq of course.
Irq sharing is possible though. My interrupt table looks like
the following and I have no problems:
0: 11296449 11304831 IO-APIC-edge timer
1: 0 2 IO-APIC-edge keyboard
2: 0 0 XT-PIC cascade
3: 7682376 7694587 IO-APIC-edge eth0
8: 2 0 IO-APIC-edge rtc
9: 4766503 4764709 IO-APIC-level advansys, aic7xxx, eth1
10: 5842 5890 IO-APIC-level advansys, aic7xxx
11: 18862 18793 IO-APIC-level advansys
12: 4 3 IO-APIC-level advansys
13: 1 0 XT-PIC fpu
14: 183701 180103 IO-APIC-edge ide0
15: 2003423 2014463 IO-APIC-edge ide1
Paul Mackinney wrote:
> Matthew Garman muttered:
> > According to the Ethernet HOWTO, the most common cause of this problem is
> > an IRQ conflict. This seems believable, because...
> > cat /proc/interrupts
> > CPU0
> > 0: 42726 XT-PIC timer
> > 1: 2024 XT-PIC keyboard
> > 2: 0 XT-PIC cascade
> > 4: 12012 XT-PIC
> > 5: 3 XT-PIC soundblaster
> > 11: 5986 XT-PIC sym53c8xx, eth0
> > 12: 4799 XT-PIC PS/2 Mouse
> > 14: 2 XT-PIC ide0
> > NMI: 0
> > ERR: 0
> > You can see that both my SCSI controller and my ethernet card live on IRQ
> > 11.
> I'm not an expert on IRQs, but my (vague!) understanding is that it's
> actually the PCI controller that uses the IRQ, so if these devices are
> on the same bus, it doesn't necessarily indicate a conflict.
> Joost is absolutely on the right track: what changed between when it
> worked and when it quit working? This should be a clue. Also, before
> pinging it from another host, make sure that ifconfig returns good info
> for eth0 and that it can ping itself at eth0's TCP/IP address--if either
> of these fail then you already know it's not talking.
> One standard trouble-shooting technique for PCI devices is to swap the
> cards into different slots.