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huntson

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Why isn't my network passing a certain vlan.

I have a network that appears not to be passing one vlan.  This is quite an odd situation.  I have a stack of switches that are made up of Cisco SGE 2000 24 and 48 port units.  My router and where all the vlans are being created is a Netgear FVS318N.

I have the standard vlan 1 plus 3,4,5, and 6.  All appear to work properly and communicate with each other as required except vlan 3.  For the simplicity of the installation and explaining it to other people - each vlan has it's own cable to the switch stack.  Obviously I have done something correctly as I'm able to ping IP addresses from one vlan to the other except for vlan 3.  Specifically vlan 3 is a 192.168.103.x subnet with a /32 subnet.  On the Cisco side I have the port coming in from the Netgear set as PVID 3 and only working with that vlan.  On the Netgear side I have it set the same.  On the Cisco side, devices on different ports that are set to vlan 3 are able to communicate with each other; same on the Netgear side.  Only issue seems to be when connecting the two.  Anyone have any idea of where to start?
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masnrock
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Is there anything done differently with VLAN 3 versus the others?
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huntson

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That would be my first thought although I can see nothing that sets vlan 3 apart in any way.  Settings and topology are the same.
> Specifically vlan 3 is a 192.168.103.x subnet with a /32 subnet.

Confirm /32 please.  My eyes say that is a particularly tiny subnet to the point of non-existance(?).
Rich is right. /32 can be typed into SOME systems to represent a single IP address. However,it can't be done for subnetting purposes. Unless you meant /24, but you might want to check the settings :)
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I meant /24.  Here I was trying to be fancy and I messed it all up!!!
Any way to see configurations of both switches, especially at the ports linking the two?
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Sure.  I have tried both port 2 and 3 on the Netgear.  They are connected to port 17 of the Cisco switch.  Note I did incorrectly post at the beginning about the subnet range completely.  It is 192.168.102.x /24
Screen-Shot-2017-04-11-at-11.14.26-A.png
Screen-Shot-2017-04-11-at-11.15.16-A.png
IMG_7417.JPG
Why does the column for port 17 on the Cisco say Disable?
Port g17 on the Cisco appears to be disabled...
Looks like Rich and I are on the same wavelength! Enable port 17, and that should resolve your issue. Everything else appears to be configured right.
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Sorry about that.  Playing around with setting sto see if anything makes a difference.  It's normalized now and still no dice.  That was referring to Ingress filtering
I assume there is no command line interface in the Cisco SGE 2000.  :-(  Can you get an equivalent screen shot on the Cisco side, like you did for the Netgear?  Confirm port status, speed/duplex, etc?
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There is a command line interface but I can't say I'm any good at it.
image1.JPG
Would it be possible to see more detail on port 17, solely in the context of VLANs? You might have to go through the VLAN settings to be able to show us. (There is a chance that changing that port to either Access or Trunk mode may do the trick) What mode are the ports that are being used to connect to the other VLANs in?
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Currently it is in access mode.  All the vlans that are being connected to the switch and the router are configured exactly the asme way.  Port 16 is one of them and port 17 is another.
Are there logs available on the switches and router?  I can't help wondering if something like spanning tree is preventing traffic from passing on the port you expect.  Seems like stp would be an unlikely cause, but I keep wondering if something else would be logging an error on one of the devices.

Any chance of seeing the filters applied on the ports?
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Very impressive Rich.  Turned off Spanning Tree on the Cisco stack and it magically worked.  Can you do your best and explain why you think that is please?
One possibility would be that you may have inadvertently created a loop somewhere, and STP blocked port 17 to prevent further issues.
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I see.  I doubt that considering how simple my setup is.
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I just wouldn't want problems to come up in the future.
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Rich Weissler

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Would STP actually shut the port down? I was seeing link lights the entire time.
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Good call again guys:  after using one cable to trunk all the Vlans I was able to reenable spanning tree with no problems.

THANKS!!!