Quick scenario.. I have a pix 506 connected to a Hp procurve switch running at 10mb half duplex. All other machines and switch settings were set to auto negotiate. Today had constant packet loss and collision. Things seemed to get better when I clear the arp tables on the pix(???) So I set everyone to 10mb half duplex and everything was back up and running. Any ideas or commments? Could a mixed environment of full and half duplex cause these issues? Does the pix have anything to do with my issues???
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half and full duplex
- Thread starter CMASPE
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Guest_imported
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- Jan 1, 1970
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Have not used pix before. But I have heard of instances of auto-negotiate not negotiating right. Seems sometimes devices just can't seem to agree with each other. Not sure if this is the case for you, but just thought I'd chime in with my 2 cents.
As GTI wrote, it is usual for some equipments not to negotiate properly when their set to "auto". This happens often when your playing with "SUN" servers and "Cisco" switches or routers, they usually don't play along very well.
I never used a pix but i see it happen all the time with other hardware providers.
I never used a pix but i see it happen all the time with other hardware providers.
Auto negotiate usually works fine IF the network cards and switch/hub are same manufacturer.
Not helpful if everything on your network is different. 3 Com NICs are usually quite good at cross vendor auto negotiate I have found, but still not 100%
But yes - the mixed environment can cause lots of collisions and general slowdown
Not helpful if everything on your network is different. 3 Com NICs are usually quite good at cross vendor auto negotiate I have found, but still not 100%
But yes - the mixed environment can cause lots of collisions and general slowdown
Guest_imported
New member
- Jan 1, 1970
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Cisco's official recommendation: disable auto negotiation. It's kind of like the old days of "Plug and Pray," don't trust it. A mixed environment of half and full duplex should work fine, I don't believe that's the issue.
jimbopalmer
Programmer
Quick Clarification: if some ports on a switch are Full duplex and some are Half, all is well. If the different ends of the same wire are not configured to the same duplex, it really slows down! I tried to remain child-like, all I acheived was childish.
I agree with the problem with auto-negotiate. If you can, set all NIC's to 100Mbit/s Full-duplex.
What I have seen is that sometimes everything works fine. There is an error now and then but re-transmit is handled fine at layer 3, but then when the load goes up on the NIC you get so many errors that everything slows down.
On a switch full-duplex is in 99,9999% of the cases the best thing to go for.
Auto-negotiate is not very stabel even with the newest hardware.
/johnny
What I have seen is that sometimes everything works fine. There is an error now and then but re-transmit is handled fine at layer 3, but then when the load goes up on the NIC you get so many errors that everything slows down.
On a switch full-duplex is in 99,9999% of the cases the best thing to go for.
Auto-negotiate is not very stabel even with the newest hardware.
/johnny
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