How do configure router-on-a-stick for multiple switches?

ravingmiceravingmice Member Posts: 8 ■□□□□□□□□□
Hi, first of all, my apologies if this post isn't in the correct forum, it's my first time/post here.

Anyway, i've attached a link to the packet tracer file below. So currently, i've set up the appropriate vlans on all the access switches, i've also set up the trunk ports from the access switches to the distributor switches. In addition, i've also configured the sub-interfaces on the router. At the moment, the "server" end devices are able to ping each other. however, all the other end devices can't seem to do the same. I was hoping someone with more knowledge could help me out. I don't want answers per se, just what i have done wrong so i can learn and fix it. P.s the console password is "cisco" and enable password is "class" if you need to see the configurations.

Thank you so much in advance.


  • EANxEANx Member Posts: 1,077 ■■■■■■■■□□
    I'm not going to open a packet tracer file but I'll ask some questions to get you thinking. I'm not asking for output responses. When troubleshooting, I like to start at the bottom of the OSI model.

    Do you have connectivity between the switches? Does "show CDP neighbor detail" work as expected?
    Are you using DHCP? If so, are the devices getting an address? If not, where's the server and is an ip helper needed?
    Are the default gateways configured correctly?
    What does the arp table look like?
  • alan2308alan2308 Member Posts: 1,854 ■■■■■■■■□□
    You'll probably get a lot more views of your topology if you take a screenshot and give a little detail on what you've done so far. I don't have packet tracer installed on my computer and I'm not going to install it just to look at your file.

    But basically, if you have router on a stick set up correctly between the router and the switch that it's plugged into, and you have the trunks set up correctly between all the switches, then you should have full network connectivity. EANx is right, start at layer 1 and work your way up, but my guess would be the trunk between the router and the switch that its connected to.
  • ravingmiceravingmice Member Posts: 8 ■□□□□□□□□□
    Oh, Thank you for the advice. Again, my apologies, i'm studying this independently so everything i've done so far is based on what i learned on youtube. I've inserted some images of the errors im getting, as well as what i've done so far. So, i've got 2 distributor switches and 3 access switches. The access switches are connected to the distributors and are configured to be trunk links between the them. I've also sub-netted the IP into a /26cidr, sales and HR are both in different subnets. I was able to get each end device to ping their respective subnets prior to adding the vlans. i've configured the router to be a "Router on a stick". with subinterfaces for the vlans as well. The thing is, the HR server and sales server are able to ping each, even though they're in different vlans, which is the desired outcome in this case. However, The pc's cannot ping each or the servers for that matter. When i send a packet from, say sales pc 1, the access switch sends out an arp request to the distributor switches. However, the distributor switches always drop the packet. They don't forward it :/ I've set them all to be trunk ports...I hope that gives a little bit of insight as to what i may be doing wrong. Thanks heaps by the way. On the simulator it says " The active VLAN interface is not up. The ARP process ignores the frame." "Switch does not have the VLAN indicated on the IEEE 802.1q frame tag. It drops the frame."
  • ravingmiceravingmice Member Posts: 8 ■□□□□□□□□□
    Screenshot__2_.htmlScreenshot__3_.htmlScreenshot__4_.htmlHere are the screenshots, i attached it to the comment but i'm not sure if it worked, but the 4shared link is below
  • ravingmiceravingmice Member Posts: 8 ■□□□□□□□□□
    hi EANx, well, before i connected the vlans, yes. They were all talking to each other, I was able to ping end devices on different switches. However, after configuring the vlans, they all stopped working....except for the Server devices, which are directly connected to "access 3", the servers are in different subnets and vlans, but can still talk to each other...which is good. but the other pc's can't. I'm guessing it's probably because the "access 3" switch is the only switch directly connected to the Router, so it doesn't rely on the "distributor" switches as it can talk directly to the router. But the other switches aren't connected to the router, so they have to go through the "distributor" switches first. Whenever i try to send packets from say, sales PC to HR PC, the destination is is the HR Gateway (for their subnets), which i've configured on the router sub-interface. The only problem is, the packet doesn't make it to the router, It gets dropped immediately on the "distributor" switches. And im a little confused because the trunk ports are all up.
  • ravingmiceravingmice Member Posts: 8 ■□□□□□□□□□
  • ravingmiceravingmice Member Posts: 8 ■□□□□□□□□□
  • ravingmiceravingmice Member Posts: 8 ■□□□□□□□□□
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