LinuxQuestions.org
Welcome to the most active Linux Forum on the web.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Newbie
User Name
Password
Linux - Newbie This Linux forum is for members that are new to Linux.
Just starting out and have a question? If it is not in the man pages or the how-to's this is the place!

Notices


Reply
  Search this Thread
Old 12-03-2011, 11:09 PM   #1
Jae-Yong Yoo
LQ Newbie
 
Registered: Jul 2011
Posts: 20

Rep: Reputation: Disabled
About irq number of network interface


if I type ifconfig eth0, it shows the following

$ ifconfig eth0

eth0 Link encap:Ethernet HWaddr b8:ac:6f:0c:7e:7e
inet addr:203.237.53.103 Bcast:0.0.0.0 Mask:255.255.255.0
inet6 addr: fe80::baac:6fff:fe0c:7e7e/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:50282914 errors:0 dropped:0 overruns:0 frame:0
TX packets:47054189 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:12732118873 (12.7 GB) TX bytes:34827877340 (34.8 GB)
Interrupt:21 Memory:fe9e0000-fea00000


In the last line, it says Interrupt:21.
What does this number 21 mean? I don't think it is the irq number since the /proc/interrups says differently

$ cat /proc/interrupts | grep 'CPU\|eth'

CPU0 CPU1
42: 62179752 28 PCI-MSI-edge eth0


Any answers would be appreciated.
 
Old 12-04-2011, 09:56 AM   #2
business_kid
LQ Guru
 
Registered: Jan 2006
Location: Ireland
Distribution: Slackware & Android
Posts: 7,796

Rep: Reputation: 754Reputation: 754Reputation: 754Reputation: 754Reputation: 754Reputation: 754Reputation: 754
If eth0 is working, don't worry.

I had issues in the past with a nic not working over an interrupt, and it needed 'acpi=off' on the boot line. That's not always wise today. What is the nic?

The numbers of irqs increased as PCs progressed. The IBM XT had 8 (One 8259); The AT had 16, and there it stayed for a while(Two 8259s, one fed into the other); Then we had 24 (virtual 8259s were put into some ASIC) and interrupt sharing. Boxes often assign half-assed irqs to things, and it affects old hardware. 48 seems excessive but we could be up there.
 
  


Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
What is the relation ship between vector and irq number? eric_tj Linux - General 1 12-10-2010 09:54 AM
Network Interface IRQ address fullgore Slackware 3 04-04-2008 08:27 AM
two nics; inconsistent network interface number assignment schatoor Linux - General 2 02-14-2007 10:25 AM
How to find irq number associated with PCI interrupt P.S.R.K.S.PRASAD Linux - Kernel 3 11-09-2006 12:33 AM
Obtain the real IRQ number for a PCI device Elliott-t Linux - Kernel 2 09-24-2006 10:05 PM


All times are GMT -5. The time now is 08:41 PM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration