Re: [Devil-Linux-discuss] VLAN & routing. Poor performance

[Martin H. <ma...@ho...>]

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and what happens if you use 2 VLANs, both tagged or one tagged and one =
untagged? At least you would do so in the switching world.
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#m

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Von: dev...@li... im Auftrag von =
John Jore
Gesendet: Sa 11.08.2007 21:47
An: dev...@li...
Betreff: [Devil-Linux-discuss] VLAN & routing. Poor performance



Hi!

I've got a VMware VM with 2 NICs, vmxnet/e1000's.  On each side there is =
another VM running Windows. I map and browse a share on one from the =
other, using the DL VM as a router.

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1: When both NICs are running in "normal" mode, no VLANs, speed is =
good/normal.

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2: When one NIC is running as "normal" and one as a VLAN card, (vmxnet =
and e1000 both support this). Speed is horrible and barely works. I can =
browse the root of the share, but it soon times-out and can't browse the =
share and looses all SMB connectivity with the host. Ping seems to be ok =
though, with both small and large packets.=20

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3: Remove/disable one NIC and run all traffic as VLAN traffic over the =
remaining card (router-on-a-stick): Speed is good/normal.

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What is going on?!? And why am I seeing this? I'm using version 1.2.13 =
of DL.=20

To repeat myself just in case: When a packet arrives on the normal NIC =
and gets routed to the VLAN'ed NIC and exits DL performance is horrible.

Could there be a problem with the Linux kernel version when doing =
routing from a "non-VLAN'ed" NIC to a "VLAN'ed" NIC? The configuration =
of the nic's themselves can't really be wrong as Ping works, end-to-end. =
I've tried reducing the MTU as some sites have suggested, but did not =
solve anything. Also, I do not think neither vmxnet or e1000 have the =
MTU problem with VLANs.

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Anyone have any suggestions?

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Regards,

John Jore

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PS: The firewall was enabled, but it's not doing much, and it's =
configuration did not change between these three setup's (enabled =
traffic on all interfaces, both vlan's and physical and filtered on IP =
addresses only) I would therefore not blame it in this case.

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