Very Computer

Hi I run Slack 8.0 with kernel 2.4.16 and compiled Vlan 802.1q with a
patched eepro100 network card/driver (needed for vlan functionality).

I have made 3 vlans and patched them into a Cisco Catalyst switch wich also
i configured to hande the same vlans.

The trunk works nicely, but performance is terrible. I have full duplex
100mbit connection, but data flow is at its best 4000kbit/s. The linux
computer has pIII 700MHz and 400MB of RAM. Top tells me that the computer is
close to idle.

ifconfig tells me that there are alot of collisions on the "mother"
interface of a vlan. For inst. eth0 is the mother interface, and eth0.2,
eth0.3 and eth0.4 is the child interfaces. The child interfaces have no
collisions. Here is the output of the eth0 ifconfig:

eth0      Link encap:Ethernet  HWaddr 00:D0:B7:48:10:53
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:2215674 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1665380 errors:0 dropped:0 overruns:0 carrier:35039
          collisions:58047 txqueuelen:100
          RX bytes:774221949 (738.3 Mb)  TX bytes:1123953235 (1071.8 Mb)
          Interrupt:11 Base address:0x1000

Anyone any ideas abot this weidrness??

Best regards
Stian B. Barmen

I believe IEEE 802.1q is actually able to manage only 10 Mbit/s VLAN
trunk segments.
This could explain the amount of collisions you encounter.
Standing on what I know cisco catalyst switches use a particular cisco
protocol to connect 100 Mbit VLANs (I cannot actually remember it's name...)

Am I right? :-/

--
Emanuele "SKULL" Balla
--------------------------------------------------------------------
Internet e' una pippa planetaria, un collettore delle frustrazioni di
40 milioni di persone.  -- Bruno Gambarotta, 20/2/1997, RaiUno

Quote:

> >Hi I run Slack 8.0 with kernel 2.4.16 and compiled Vlan 802.1q with a
> >patched eepro100 network card/driver (needed for vlan functionality).

> >I have made 3 vlans and patched them into a Cisco Catalyst switch wich
also
> >i configured to hande the same vlans.

> >The trunk works nicely, but performance is terrible. I have full duplex
> >100mbit connection, but data flow is at its best 4000kbit/s. The linux
> >computer has pIII 700MHz and 400MB of RAM. Top tells me that the computer
is
> >close to idle.

> I believe IEEE 802.1q is actually able to manage only 10 Mbit/s VLAN
> trunk segments.
> This could explain the amount of collisions you encounter.
> Standing on what I know cisco catalyst switches use a particular cisco
> protocol to connect 100 Mbit VLANs (I cannot actually remember it's
name...)

> Am I right? :-/

I connected a Cisco 7206 to a Nortel switch and was able to get full speed
at 100Mbit between these two. Also I connected the same router to the
Catalyst switch, also 100Mbit, no problem. The Linux machine connected to
either of these switches produces only about 7Mbit at the very best speeds.

Hope there is a way to get my Linux box to push more data ... !

Best regards
Stian B. Barmen

Hi Skull !

I believe not, tagging has nothing to do with speed.
It should come from very subtle reasons, perhaps commutation speed for
Linux network interface... It will not be easy to fix anyway.

Quote:> Standing on what I know cisco catalyst switches use a particular cisco
> protocol to connect 100 Mbit VLANs (I cannot actually remember it's
> name...)

This is called ISL (Inter Switch Link) for relaying tagging policy
between switches on trunk ports only, very same as 802.1q but
proprietary Cisco stuff, but Cisco stuff has both of them anyway.

Ciao !

How did you set up the connection?  Cisco in particular is very picky about
speed/duplex.  Both sides must be set to auto, or else both sides must
specify exacly the same settings.  You cannot mix auto settings.  In other
words if you explicitly set the speed, you must also set the duplex - you
can't use auto for only 1 of the parameters.

Quote:

> > I believe IEEE 802.1q is actually able to manage only 10 Mbit/s VLAN
> > trunk segments.
> > This could explain the amount of collisions you encounter.
> > Standing on what I know cisco catalyst switches use a particular cisco
> > protocol to connect 100 Mbit VLANs (I cannot actually remember it's
> name...)

> > Am I right? :-/

> I connected a Cisco 7206 to a Nortel switch and was able to get full speed
> at 100Mbit between these two. Also I connected the same router to the
> Catalyst switch, also 100Mbit, no problem. The Linux machine connected to
> either of these switches produces only about 7Mbit at the very best

speeds.

You connected the 7206 as a trunked connection using 802.1q?  If not, I'd
say it didn't test the same things.

Quote:

> Hope there is a way to get my Linux box to push more data ... !

> Best regards
> Stian B. Barmen

Quote:

> I believe not, tagging has nothing to do with speed.
> It should come from very subtle reasons, perhaps commutation speed for
> Linux network interface... It will not be easy to fix anyway.

Do you think I will need to buy myself a new network interface (I have now
tried 2 intel eepro100 cards, in 2 diffrent switches, one Cisco and one
Nortel, all configs have the same problem), or is it a kernel, I/O problem
or do you have other suggestions?

Quote:

> > Standing on what I know cisco catalyst switches use a particular cisco
> > protocol to connect 100 Mbit VLANs (I cannot actually remember it's
> > name...)

> This is called ISL (Inter Switch Link) for relaying tagging policy
> between switches on trunk ports only, very same as 802.1q but
> proprietary Cisco stuff, but Cisco stuff has both of them anyway.

> Ciao !

I can also mention that I have tried the 2.4.18pre2 kernel, same result.
Running out of ideas...!

Best regards
Stian B. Barmen

Hi Stian !

I suggest anyway you wait before spending too much money about this.
This is a really complicated matter, an affordable solution may be
allready present, or perhaps not, so let time a chance so as to find out.
In case you really want to make a last try, you might want to use 3Com
NIC, I will buy myself 2 3C905C because it seems possible to use VLAN
with them without any patch.

I forgot a last thing : this trouble me be because of 10/100 Mbps
synchronisation between interfaces, there are 4 modes for Cisco stuff
for trunk linking if I remember proberly. Whet is more I heard somewhere
  that when you use both 10 ans 100 Mbps NIC together in the same
network there are many collisions provoked by one card which emits too
many frames on purpose so as to downgrade the network to a speed level
compatible with 10 Mbps. I never saw anything like this, but the guy who
told this seemed to know the subject.

Best regards.

Quote:> I suggest anyway you wait before spending too much money about this.
> This is a really complicated matter, an affordable solution may be
> allready present, or perhaps not, so let time a chance so as to find out.
> In case you really want to make a last try, you might want to use 3Com
> NIC, I will buy myself 2 3C905C because it seems possible to use VLAN
> with them without any patch.

> I forgot a last thing : this trouble me be because of 10/100 Mbps
> synchronisation between interfaces, there are 4 modes for Cisco stuff
> for trunk linking if I remember proberly. Whet is more I heard somewhere
>   that when you use both 10 ans 100 Mbps NIC together in the same
> network there are many collisions provoked by one card which emits too
> many frames on purpose so as to downgrade the network to a speed level
> compatible with 10 Mbps. I never saw anything like this, but the guy who
> told this seemed to know the subject.

We have now tried a 3c905B PCI card without VLAN and gave it an IP,
installed FTP and tried a local file transfer. To my surprise I only got
about 2Mbit transfer, on the local LAN, 100Mbit FullDuplex...! Go figure.

-stian

Quote:> We have now tried a 3c905B PCI card without VLAN and gave it an IP,
> installed FTP and tried a local file transfer. To my surprise I only got
> about 2Mbit transfer, on the local LAN, 100Mbit FullDuplex...! Go figure.

Try a CrossOver Cable and check the card if it is running in the rightr mode
(mii-tool) and if it has errors (ifconfig).

Greetings
Bernd