Simplest way to see what speed ethernet is using?
I'm sure I asked this some time ago (i.e. some years ago!) and used the recommended program to check if all my ethernet links were actually running at the spped they were supposedly capable of. I want to check again and I can't find/remember the program to use. I have found ethtool which tells me the speed of a specific port on the system where it is running but I seem to remember there was a tool which somehow checked both ends of a link and told me that the remote end speed as well. That's the remote end at the other side of routers, switches etc. Maybe I'm imagining it as I don't really see *how* such a tool could work. The basic requirement at the moment is that I want to check that the link to my backup system in the garage is still running at full Gigabit speed. The remote system is fairly limited and, although I have ssh access to it, I can't find ethtool or an equivalent for it. -- Chris Green
On 16/01/14 11:59, Chris Green wrote:
I'm sure I asked this some time ago (i.e. some years ago!) and used the recommended program to check if all my ethernet links were actually running at the spped they were supposedly capable of.
Fairly sure that this is not quite what you were after, but it reminded me of a time when I was with Demon internet, in the infancy of broadband, before speed checking websites. The way of testing download speeds was to use FTP and download a file usually called "FullFile" from their FTP server. You know the size; you time it and a swift bit of maths gives you the transfer speed, and an indication of the speed of your internet connection. You could download one of these files and use something (cp, scp, ftp) to send it to and from your backup system from your main system and get an idea of the transfer speed. *BEWARE* speed will be limited by the slowest component, so if the source FTP server is running slow, your download will be slow and so you may not get a true indication of the speed of your network. Googling Fullfile gave me this list: http://www.filewatcher.com/m/fullfile.102400-0.html including Demon, but also debian. Looking at debian gave http://www.filewatcher.com/b/ftp/ftp.debian.nl/pub/Demon/test-0.html There are several FullFiles here of different sizes. Also EmptyFiles and RegularFiles. Why? Back in the day, V92 56K modems started using compression to increase download speeds. An EmptyFile contains only spaces, or something else highly compressible, and so would download quickly. A FullFile contains info that is deliberately hard to compress, and so gave a "worst case" (slowest) download speed. A RegularFile was designed to be a typical file (if one of those actually exists!) Once you're transferring a file, the program iftop may help. e.g. sudo iftop -i eth0 will show transfers to/from ip addresses happening over that Ethernet interface. Replace eth0 with the name of the interface you want to check. Sudo for a debian/ubuntu style O/S. su for Fedora based. HTH Steve
On Jan 16, 2014 12:00 PM, "Chris Green" <cl@isbd.net> wrote:
I'm sure I asked this some time ago (i.e. some years ago!) and used the recommended program to check if all my ethernet links were actually running at the spped they were supposedly capable of.
I want to check again and I can't find/remember the program to use.
I have found ethtool which tells me the speed of a specific port on the system where it is running but I seem to remember there was a tool which somehow checked both ends of a link and told me that the remote end speed as well.
Iperf? Regards Srdjan
On Thu, Jan 16, 2014 at 12:38:11PM +0000, Srdjan Todorovic wrote:
On Jan 16, 2014 12:00 PM, "Chris Green" <[1]cl@isbd.net> wrote:
I'm sure I asked this some time ago (i.e. some years ago!) and used the recommended program to check if all my ethernet links were actually running at the spped they were supposedly capable of.
I want to check again and I can't find/remember the program to use.
I have found ethtool which tells me the speed of a specific port on the system where it is running but I seem to remember there was a tool which somehow checked both ends of a link and told me that the remote end speed as well.
Iperf?
Possibly! :-) It happens that iperf is available to install on the backup system so I can have it at both ends as it were. -- Chris Green
participants (3)
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Chris Green -
Srdjan Todorovic -
steve-ALUG＠hst.me.uk