At 10:38 AM 3/4/99 -0800, Dane Jasper wrote:

On Thu, Mar 04, 1999 at 09:19:36AM -0000, Garrett Burke wrote:

...

As an aside, have you run a filer into a 100Mb/s port on a S48? I'm seeing CRC errors on the port that my F230 is on. Netapp are investigating, just wondering if anyone else is seeing/has seen this.

We've got a F230 running 100-FD with a Summit 48. We found that we had better results if we hard set both devices to 100-FD and turned off negotiation.

The F200/F300 series on-board ethernet doesnot autonegotiate. So if you had the filer's ethernet interface set to operate in 100BaseTx-FD, the corresponding switch port should also be set to operate in 100BaseTX-FD.

When speed/duplex mismatches occur, depending on the switch to which the filer's interface is connected, you will see CRC errors and collisions. You will definitely see poor network throughput.

Here is a table that gives info on the board types and the supported speed and duplex (mediatype)

Interface Sysconfig name Mkt P/N Mediatype --------- -------------- ------- --------- Single 10/100 - ZX342 - X1001 - 10BaseT(half/full), 100BaseTx(half/full) Quad 10 BaseT - ZX314 - X1002 - 10BaseT(half/full) Quad 10 BaseT - ZX314 - X1003 - 10BaseT(half/full) Quad 10/100 - ZX346 - X1012 - 10BaseT(half/full), 100BaseTx(half/full), auto Single 10/100 - ZX345Q - X1001B - 10BaseT(half/full), 100BaseTx(half/full), auto Quad 10/100 - ZX346Q - X1012B - 10BaseT(half/full), 100BaseTx(half/full), auto F200/300 series onboard - 10BaseT(half/full), 100BaseTx(half/full) F700 series onboard - 10BaseT(half/full), 100BaseTx(half/full), auto

Here is a small note on autonegotiation in the ethernet world:

Q. What is Auto-negotiation? A. Auto-negotiation is an optional function of the IEEE 802.3u Fast Ethernet standard that enables devices to automatically exchange information over a link about their speed and duplex abilities. This allows devices to perform automatic configuration to achieve the maximum common level of operation over a link.

Q. How does Auto-Negotiation work at Both Ends? A. When two auto-negotiation devices with multiple capabilities are linked together, they find their maximum common mode of operation based on a priority table.

The following table lists priorities from the highest (1) to the lowest (5). The full-duplex mode of operation is given higher priority over half-duplex because, at the same speed, more data can traverse the full-duplex link.

------------------------------------------------------- Priority Capabilities ------------------------------------------------------- 1 100BaseT4 (not supported on NetApp filers) 2 100BaseTX Full Duplex 3 100BaseTX 4 10BaseT Full Duplex 5 10BaseT --------------------------------------------------------

Q. How does Auto-Negotiation work at One End? A. If one link partner is set to auto-negotiate and the other link partner is manually set, the manually set partner must always be half-duplex.The IEEE spec does not allow the auto-negotiating partner to detect full-duplex on a manually set link partner.

auto ----X--> 100BaseT-FD auto -------> 100BaseT-HD

If one end is configured to operate in 100BaseTx fullduplex make sure that the other end is also manually configured to operate in the same mode.

If there is a speed/duplex mismatch, you might see CRC errors and poor network throughput.

Hope this helps.

-Devi Network Appliance