Re: Vexing Behavior: RHEL 5.2 (2.6.18-92) Random NIC Enumeration Between Reboots

John Haxby wrote:

> We were talking about this here the other day. You obviously know  
> about the issues of hardware discovery changing from one kernel  
> release to another and the whether you do a breadth-first search or  
> a depth-first search.
> The particular case we were talking about was that the hardware  
> doesn't do PCI device detection in a deterministic fashion under  
> some circumstances. It's not quite random, but it's variable enough  
> to bevexing. I'm afraid you're stuck with using HWADDR in the ifcfg- 
> eth* files or using a similar device uuid to distinguish one NIC  
> from another. We suspect that this random behaviour will become the  
> norm in future.
> jch
I have a number of Dell systems, running RHEL5.2 suffering badly from  
this issue. They all have two on-board NICs and one or two 2-port or 4- 
port PCI cards.

I can't set HWADDR in the ifcfg-eth* files because most of the NICs  
are in bonded pairs and it is the ifcfg-bond* which has a HWADDR which  
is shared between the two NICs which are slaves to that bond*.

I've just discovered the pci=bfsort kernel parameter yesterday and  
begun to configure it on the systems, but it is too early to say if it  
works, as the issue is random at boot time.

I had no luck configuring udev/rules.d to do HWADDR matching using  
rules like:
KERNEL=="eth*",DRIVER=="bnx2",SYSFS{address}=="00:1d:09:1e:b0:a9",  
NAME="eth0"
It seemed to be ignored.

JZ