We actually opened an issue with IBM over this. Here's what I got back:
Action Taken...: The ethtool utility is not supported with all device drivers as noted in the man page. It's very typical that for an gigabit NIC (especially a fiber connection) will not have a valid speed reported or no speed reported at all. To some degree it makes a bit of sense as a gigabit card is exactly that, 1GB. That is you can't tell a 1GB FIBER card to run at 10MB. Granted what gets reported by ethtool (really what th device driver is returning is mis-leading). Here is another example .. a very simple Tigon3 GB NIC, note the speed it reported as Unknown! [EMAIL PROTECTED] ~]# ethtool eth0 Settings for eth0: Supported ports: [ FIBRE ] Supported link modes: 1000baseT/Half 1000baseT/Full Supports auto-negotiation: Yes Advertised link modes: 1000baseT/Half 1000baseT/Full Advertised auto-negotiation: Yes Speed: Unknown! (0) Duplex: Half Port: FIBRE mii-tool is only valid for mii compatable NIC cards. If the goal is to do some performance testing, then the best method is to use the netperf tools. ( see http://www.netperf.org) Another simple test is using dd and ftp, for example: # ftp <hostname_of_server> ftp> bin ftp> put "| dd if=/dev/zero bs=32k count=10000" /dev/null Using either of these tools should confirm that the NICS are transfering far faster the 10MB. So in other words, the gigabit OSA can only run at a gigabit, the tools are useless for this application, and the only way to be sure about the throughput is to measure it. -----Original Message----- From: Linux on 390 Port [mailto:[EMAIL PROTECTED] On Behalf Of Mark Post Sent: Monday, September 29, 2008 12:14 PM To: LINUX-390@VM.MARIST.EDU Subject: Re: [LINUX-390] Gigabit interface on Linux? >>> On 9/29/2008 at 12:02 PM, in message <[EMAIL PROTECTED]>, Scott Rohling <[EMAIL PROTECTED]> wrote: > On RHEL5.2 -- we're using mii-tools and seeing that the ethernet interface > is set to 100mbs -- the OSA is set to gigabit - and we're wondering if > something special needs to be done to set it to gigabit speeds.. Using > 'ethtool=' doesn't seem to work on Linux (s390x linux).. I'm amazed that mii-tools returns anything at all. > This is on a VSWITCH -- everything works fine except the reported speed... > Any ideas? Since the interface that mii-tools is reporting on is a virtual one, having nothing to do with any real hardware, I would say ignore it. Mark Post ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 -------------------------------------------------------- This message w/attachments (message) may be privileged, confidential or proprietary, and if you are not an intended recipient, please notify the sender, do not use or share it and delete it. Unless specifically indicated, this message is not an offer to sell or a solicitation of any investment products or other financial product or service, an official confirmation of any transaction, or an official statement of Merrill Lynch. Subject to applicable law, Merrill Lynch may monitor, review and retain e-communications (EC) traveling through its networks/systems. The laws of the country of each sender/recipient may impact the handling of EC, and EC may be archived, supervised and produced in countries other than the country in which you are located. This message cannot be guaranteed to be secure or error-free. This message is subject to terms available at the following link: http://www.ml.com/e-communications_terms/. By messaging with Merrill Lynch you consent to the foregoing. -------------------------------------------------------- ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390