Is there any objective info, good or bad, on other low end ethernet chips,
like the Davicom DM9102 or the Sis 900? Realtek/Davicom/Sis-based NICs sell
for 4-5 dollars each down here, so they're usually what you'll find in small
setups like router/firewall boxes.

-----Original Message-----
From: Fleming, John (ZeroChaos) [mailto:[EMAIL PROTECTED] 
Sent: Friday, August 19, 2005 9:15 AM
To: Scott Ullrich; M. Kohn
Cc: [email protected]
Subject: RE: [pfSense-discussion] Multi-WAN and routable subnets...

Speaking rl nics we should post this somewhere in the faq section on why we
don't like rl nics.

This is from the driver's source.
/usr/src/sys/pci/if_rl.c

/*
 * The RealTek 8139 PCI NIC redefines the meaning of 'low end.' This is
 * probably the worst PCI ethernet controller ever made, with the possible
 * exception of the FEAST chip made by SMC. The 8139 supports bus-master
 * DMA, but it has a terrible interface that nullifies any performance
 * gains that bus-master DMA usually offers.
 *
 * For transmission, the chip offers a series of four TX descriptor
 * registers. Each transmit frame must be in a contiguous buffer, aligned
 * on a longword (32-bit) boundary. This means we almost always have to
 * do mbuf copies in order to transmit a frame, except in the unlikely
 * case where a) the packet fits into a single mbuf, and b) the packet
 * is 32-bit aligned within the mbuf's data area. The presence of only
 * four descriptor registers means that we can never have more than four
 * packets queued for transmission at any one time.
 *
 * Reception is not much better. The driver has to allocate a single large
 * buffer area (up to 64K in size) into which the chip will DMA received
 * frames. Because we don't know where within this region received packets
 * will begin or end, we have no choice but to copy data from the buffer
 * area into mbufs in order to pass the packets up to the higher protocol
 * levels.
 *
 * It's impossible given this rotten design to really achieve decent
 * performance at 100Mbps, unless you happen to have a 400Mhz PII or
 * some equally overmuscled CPU to drive it.
 *
 * On the bright side, the 8139 does have a built-in PHY, although
 * rather than using an MDIO serial interface like most other NICs, the
 * PHY registers are directly accessible through the 8139's register
 * space. The 8139 supports autonegotiation, as well as a 64-bit multicast
 * filter.
 *
 * The 8129 chip is an older version of the 8139 that uses an external PHY
 * chip. The 8129 has a serial MDIO interface for accessing the MII where
 * the 8139 lets you directly access the on-board PHY registers. We need
 * to select which interface to use depending on the chip type.
 */

-----Original Message-----
From: Scott Ullrich [mailto:[EMAIL PROTECTED]
Sent: Friday, August 19, 2005 8:52 AM
To: M. Kohn
Cc: [email protected]
Subject: Re: [pfSense-discussion] Multi-WAN and routable subnets...

Right now a minimum of 3 public ips will be required between the two
boxes:

2 - Each machine will share one REAL ip
1 - Each machine will both share one virtual ip
-------------------------------------------------------------------
3 total needed

Carpdev changes this to need 1 total for both hosts but this is not ready in
FreeBSD just yet.

Scott


On 8/19/05, M. Kohn <[EMAIL PROTECTED]> wrote:
> We have a dual WAN setup (WAN and OPT1).
> Every WAN interface takes a /29 subnet.
> We have also an additionaly /29 subnet, which is routable (to the DMZ) 
> for every WAN.
> In addition to that we also have an private class-C net for our DMZ.
> 
> So I need to setup the DMZ with three different subnets, one outgoing 
> NAT and two routable.
> 
> I setup DMZ interface with real IP and right netmask, which works 
> (extended NAT aktivated).
> Than I tested adding a CARP virtual IP with /32, or CARP virtual IP 
> with /29 from the other subnet but no success...
> 
> The CARP (failover) status page shows no MASTER and no carp interface 
> for this. And an ifconfig shows the carpX interface with no IP.
> 
> I fear it is the same problem missing carpdev patch from OpenBSD like 
> Bill wrote yesterday, is it?
> 
> 
> Regards,
> Michael
> 
> 
>

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