Solved

ping layer 3 switch and hosts

Posted on 2013-12-31
9
904 Views
Last Modified: 2014-01-08
I have a lab with different networks and on one network I have a layer 2 and layer 3 switch, the layer 3 switch is connected to a router. I have a few different vlans on this network. All vlans can communicate with each other and the switches and router.

I can ping externally to another client on another network form the layer 3 switch with no problem. However, I cannot ping from the layer 2 switch or computers on the vlans on the same network to these external hosts. What is it that is preventing replies when I ping externally?
There are no acl's on the routers.
0
Comment
Question by:tolinrome
  • 4
  • 3
  • 2
9 Comments
 
LVL 9

Expert Comment

by:Trenton Knew
ID: 39749125
is the switchport access mode to the router a trunk or is it only assigned to one vlan?  If the layer 3 switch is not routing inter-vlan traffic, the port connected to the router will have to be trunked, and the router itself will have to support inter-vlan routing and trunking.
0
 
LVL 9

Expert Comment

by:Trenton Knew
ID: 39749129
are there multiple vlans on the layer 2 switch also?  is the switchport access mode between the port on the L2 switch and L3 switch trunked as well?
0
 
LVL 17

Expert Comment

by:jburgaard
ID: 39749166
Best gues is a missing route back on router to vlan with problem.

But please provide details: IP, dgw. and net-mask for a client with problem.
For L3-switch: IP & net-mask for involved vlans and dgw.
for router:IP & net-mask for involved vlans and IP routes back to client-network.
0
 
LVL 7

Author Comment

by:tolinrome
ID: 39749179
L3 switch is the DG for the vlans, I set up int vlans XX on it as below:
10.1.10.1
10..120.1
10.1.30.1 and etc

L2 switch has these vlans as well (obviously not int vlans, just vlans). host computers are connect to the L2 switch only.
On the L3 switch there is the "ip routing" command for internal vlan routing and the statement "ip route 0.0.0.0 0.0.0.0 10.1.60.2" which 10.1.60.2 is the internal interface of the router. Vlan 60 is the vlan that connects the L3 switch to the router. It is only 2 interfaces, the L3 switch and router.
0
Better Security Awareness With Threat Intelligence

See how one of the leading financial services organizations uses Recorded Future as part of a holistic threat intelligence program to promote security awareness and proactively and efficiently identify threats.

 
LVL 17

Expert Comment

by:jburgaard
ID: 39749223
So you have a number of networks with net-mask 255.255.255.0
your dgw of L3-sw is 10.1.60.2
For packets to come back from your router there must exist 'routes back' like
IP ROUTE 10.1.10.0  netmask 255.255.255.0  gw 10.1.60.1
The syntax probably is not exact , but to reach an address in the 10.1.10.0/24 range a packet arriving at router has no directly connected network to turn to and should not go via dgw (to internet) but via L3-switch.
Instead of a lot of routes like that you probably can bundle them with a broader net-mask than 255.255.255.0
HTH
0
 
LVL 7

Author Comment

by:tolinrome
ID: 39749375
I already had "ip route 10.1.0.0 255.255.0.0 10.1.60.1" and it wasn't working and now I added:
R1(config)#ip route 10.1.20.0 255.255.255.0 10.1.60.1
R1(config)#ip route 10.1.30.0 255.255.255.0 10.1.60.1
R1(config)#ip route 10.1.10.0 255.255.255.0 10.1.60.1
R1(config)#ip route 10.1.40.0 255.255.255.0 10.1.60.1

and it still doesn't work.
0
 
LVL 17

Expert Comment

by:jburgaard
ID: 39749833
Could a there be a firewall-rule on the destination PC?
Did you try disable firewall or pinging printer instead of PC?
Did you try traceroute/tracert both ways?
0
 
LVL 7

Accepted Solution

by:
tolinrome earned 0 total points
ID: 39749945
Problem solved. On the L3 switch, not the router, I had to use the "#network 10.1.x.0 0.0.0.255 area 0" for ospf, which then relayed those networks to the router and so on.
0
 
LVL 7

Author Closing Comment

by:tolinrome
ID: 39764692
This was the solution.
0

Featured Post

How your wiki can always stay up-to-date

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

Join & Write a Comment

I recently attended Cisco Live! in Las Vegas, a conference that boasted over 28,000 techies in attendance, and a week of hands-on learning hosted by a solid partner with which Concerto goes to market.  Every year, Cisco displays cutting-edge technol…
ADCs have gained traction within the last decade, largely due to increased demand for legacy load balancing appliances to handle more advanced application delivery requirements and improve application performance.
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
In this tutorial you'll learn about bandwidth monitoring with flows and packet sniffing with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're interested in additional methods for monitoring bandwidt…

708 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

18 Experts available now in Live!

Get 1:1 Help Now