How to tell if network adapter is 10 or 100MB/s?

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jonez
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Joined: 2008/02/04 18:49:22

How to tell if network adapter is 10 or 100MB/s?

Post by jonez » 2008/02/04 19:03:18

I just setup my first CentOS box as a personal media server / web server for me and my room-mate, and I'm getting really slow transfer speeds between our laptops and the server. Both laptops have 10/100 802.11 a/b/g NIC's and the server has a 10/100 NIC (hardwired) into my wireless router (802.11/a/b/g).

Based on the time to copy a 700MB file across the network my guess is the server's NIC is set to 10MB/s. I'm assuming if it was running at 100MB/s it would take less then a minute to transfer a file of that size (allowing some buffer for wireless), and currently it's taking 5-10min.

How can I tell what speed the NIC is operating at?

I tried: ifconfig eth0 (nothing about speed in there)
And: dmesg | grep eth0 (says full-duplex but that could be either setting...)

Command line only please I don't have a GUI installed (CentOS 5.1 fully updated).

The server is a P3 750MHz, 256MB SDRAM, 30GB HD (not sure of RPM), made from parts of two computers I was given by my brother. It's not the fastest but it works better then I expected.

Thanks!

michaelnel
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Re: How to tell if network adapter is 10 or 100MB/s?

Post by michaelnel » 2008/02/04 19:08:42

[code]# ethtool eth0

Settings for eth0:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supports auto-negotiation: Yes
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Advertised auto-negotiation: Yes
Speed: 1000Mb/s
Duplex: Full
Port: Twisted Pair
PHYAD: 1
Transceiver: internal
Auto-negotiation: on
Supports Wake-on: g
Wake-on: d
Link detected: yes[/code]

NedSlider
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Re: How to tell if network adapter is 10 or 100MB/s?

Post by NedSlider » 2008/02/04 19:14:37

What network protocol are you using to copy the file... ftp, ssh, smb, nfs etc??

max throughputs for 10/100Mbps

10Mbps = 1.25MB/sec so 700MB needs 560secs min (or 9mins20secs)
100Mbps = 12.5MB/sec so 700MB needs 56secs min.

...and you'll never reach maximum throughput timing a file transfer (8MB/sec sustained is good on a 100Mbit connection)

So if you're transferring that file in 5-10 mins you must logically be on 100Mbit - there's no way you'd get under 10 mins on 10Mbps.

Incidentally, I've seen very similar slow transfers when using ssh (sftp) - never did work out why, always seems to top out at ~1.5MB/sec no matter what. If I were a guessing man, I'd guess you are using ssh (sftp)??

jonez
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Re: How to tell if network adapter is 10 or 100MB/s?

Post by jonez » 2008/02/04 19:47:08

I'm using Samba. What command do I type to get the output listed in post #2?

Do you think using SSH would be any faster? I guess I'm just surprised it's a *lot* slower then the Samba share we use at work. My server at home is faster (processor / RAM wise) then the one we use at work and transfers are slower. Is there anything else that could cause this?

jonez
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Re: How to tell if network adapter is 10 or 100MB/s?

Post by jonez » 2008/02/04 19:52:50

LMAO I can't believe I didn't try ethtool eth0 before I typed that... yes it's running at 100MB/s. Are there any other transfer modes that would be faster then Samba? I'm getting a 500GB HD for my server next week and plan on dumping about 300GB onto it, and by my calculations, with the speed it's going now, it's going to take a while :-D

NedSlider
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Re: How to tell if network adapter is 10 or 100MB/s?

Post by NedSlider » 2008/02/04 20:26:47

In my experience Samba is normally pretty good. Copying files in konqueror (KDE) normally reports transfer speeds of around 8MB/sec for me, so a 700MB ISO image would copy in about 90 seconds or so.

Steve_K
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Joined: 2007/10/03 09:40:42

Re: How to tell if network adapter is 10 or 100MB/s?

Post by Steve_K » 2008/02/19 10:16:45

Hi,

Don't forget you're using wireless on your laptop - if it's 802.11g mode that you're running in, then the maximum theoretical transfer rate is 54Mbps, [b]NOT[/b] 100Mbps. With wireless though, you will never get that kind of speed on a transfer, there's nearly always some form of interference and wireless is a shared medium.

By the way jonez, it's a lower case 'b' for 100M[b]b[/b]ps asin 100 Mega[b]bits[/b] per second, not [b]bytes[/b]! :-)

Cheers,
Steve

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How to tell if network adapter is 10 or 100MB/s?

Post by arrfab » 2008/02/19 17:59:21

As already mentioned in the comments, that is surely wireless' fault ..
Try to copy from your laptop to the server through normal (and sure) ethernet network and post the results ...

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