[CentOS] Linux Kernel Physical Interface Limit

Whit Blauvelt whit at transpect.com
Wed Jul 14 15:17:30 UTC 2010


On Wed, Jul 14, 2010 at 09:51:51AM -0500, Tim Nelson wrote:

> Even if the limit were lower, such as 10 physical interfaces as mentioned
> before, I have to imagine that the host system would have issues dealing
> with the number of interrupts needed to *PROPERLY* service all of those
> interfaces in addition to the other system hardware.

There may (or may not) be another problem. As of a couple of years ago, on
some Linux variants (didn't try RHEL/CentOS), I was having trouble even
getting 6 NICs (on 3 cards) to work if I had IPv6 turned on. 4 NICs worked
fine.

Filed some bug reports, and it was evident from the response that very, very
few Linux users ever go > 4 eth's on a system. Thus the lack of properly
debugged IPv6 support for that then. Fortunately I don't (yet) need IPv6.
When I do, it'll be curious to see if the bug is still there.

Whit



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