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Simple VLAN problem?? SG200 connected to RV220W

awardblvr
Level 1
Level 1

Fairly simple:

My Main VLAN 1 is not getting DHCP addresses, but any previously DHCP'd client works fine.

VLAN 2 clients get new DHCP addresses just fine and pass traffic.

Something is missing in my understanding  or config.  Any insights appreciated!!!   Here are the details.

RV220W  Router  port 1 connected to   SG200 Port 26  

     This is VLAN1

     The RV220 is set to issue DHCP addresses 192.168.1.100 - 254.

     This is the problem VLAN - when connected through the SG200 switch

VLAN Membership Table

VLAN IDDescriptionInter VLAN RoutingDevice ManagementPort 1Port 2Port 3Port 4
1DefaultEnabledEnabledUntaggedExcludedUntaggedUntagged
2FriendsEnabledEnabledExcludedUntaggedExcludedExcluded

and

Multiple VLAN Subnet Table

VLAN IDIP AddressSubnet MaskDHCP ModeDNS Proxy Status
1192.168.1.1255.255.255.0DHCP ServerEnabled
2192.168.2.1255.255.255.0DHCP ServerEnabled

Connecting a client directly to port 1 gives an expected DHCP address.  (192.168.1.101)

Connecting a client directly to port 2 gives an expected DHCP address.  (192.168.2.101)

RV220W Router Port 2 connected to SG200 Port 25

     This is VLAN2

     The RV220 is set to issue DHCP addresses 192.168.2.100-254

     This VLAN works great through the switch.  The 4 ports assigned to VLAN2 all work fine, DHCP OK, traffic OK.

The SG200 Switch is configured

Port to VAN

     VLAN 1

          All ports (except GE20-25) are Trunk and  untagged

          GE20-25 are "excluded"

     VLAN 2

          Ports GE20-25 are Trunk and untagged

          All other ports are excluded

Port VLAN membership shows  (ports GE1-18, same as 19)

GE19Trunk1UP1UP

GE20Trunk1UP1UP

GE21Trunk2UP2UP

GE22Trunk2UP2UP

GE23Trunk2UP2UP

GE24Trunk2UP2UP

GE25Trunk2UP2UP

GE26Trunk1UP1UP

So, why is the switch not able to pass on DHCP requests, grants separetely to the two different vlans?  Only one will work at a time. Sometimes when I power-cycle noth RV 220 and SG200 it will come up with the VLAN 1 ports working and the VLAN2 not working, and sometimes visa-versa.  No clue whY both DHCP servers can't feed their respective VLANS simultaneously through the switch, whereas the work fine when conecting a PC to both RV220 ports on their respective VLANS.

Thanks for your insight!

-A

2 Replies 2

dlatorre
Level 1
Level 1

Port 2 that connects to the switch should be a trunk and should pass both vlans. As well th3 native vlan should match on both sides. In this case port 2 is excluding vlan 1



Sent from Cisco Technical Support Android App

Thanks Daniel.

However I think I might have found a different solution.

First, Please remember, that I have two links between the RV220W and the SG200. I planned on separating the traffic from VLAN1 and VLAN2  between the Switch and router. I did/do not need to have this traffic on the same phystcal port on the RV220W.

With that said... I believe by having all ports everywhere in the trunk mode, "untagged", "admit all" and "Ingress Filtering Enabled", that all VLAN encapsulation is supposed to be stripped??? So that the only thing that ever sees the VLAN encapsulation is INSIDE the switch?  And when the traffic for VLAN 2 leaves the switch to the RV220W, it has no encapsulation left??  (If all ports are configured "Trunk" and all ports are used in "untagged" mode?)

Well When I set the RV220 port #2 to VLAN8 (Which SG200 doesn't care about since this is supposed to be stripped as it leaves the RV220's port 2?)... and have the SG200 ports set to VLAN2 (which RV220 doesn't know aboiy... then EVERYTHING WORKS!).

Traffic is isolated. DHCP works on the SG200's VLAN1 & 2 ports according to their DHCP server settings on the RV220W. Cool.

I just had to have the non VLAN1 traffic appear on separate VLAN ID's between the SG and the RV.

So.  This WORKS. 

What is wrong with my underdstanding?

(Just be to clean, I turned off Spanning Tree stuff (just to eliminate variables).

Thanks!

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