Want to protect your cyber security and still get fast solutions? Ask a secure question today.Go Premium

x
?
Solved

Dell Layer 3 switch - cant change out Firewall/Gateway

Posted on 2014-11-12
6
Medium Priority
?
153 Views
Last Modified: 2016-11-23
I am working on removing a Watchguard firewall that is acting as a default gateway & firewall for a network.  It is getting replaced by a Cyberoam firewall.  

I am unable to gain access to the WatchGuard's GUI/CLI as the person who supported this network before me is unwilling to give any of the credentials to the network owner or me.

Here is what I know for certain:

The WatchGuards IP is 10.1.0.254
It acts as the default gateway for all devices on all the VLANS, without it there is no internet connectivity
I believe its mask is /25 (judging by how one of the VLANs is setup)
The layer 3 switches have a default route of 0.0.0.0/0 via 10.1.0.254
The WatchGuard receives the incoming WAN connection via a bridged ISP cable modem
From the WatchGuard the next hop is a Dell Layer 3 switch's Gigabit "Stack" port


Here is the problem:

I configured the cyberoam's WAN interface to work with the public IP range which I have confirmed with the ISP.  I configured the cyberoams LAN interface to be 10.1.0.254 /25.  I removed the WatchGuard and put the Cyberoam in its place.  At this point, the Cyberoam (with its 10.1.0.254 LAN interface) does not show up on the network.  Ping'ing 10.1.0.254 from a workstation yields nothing.  Pinging it from a L2 switch yields nothing.  If I plug my laptop directly into the Cyberoams LAN port and configure my laptop to use it as my gateway I am able to A) ping the cyberoam and B) get out to the internet.  The issue appears to be with the next hop (the Dell L3 switch).  

Putting the WatchGuard back in place and powering it on restores connectivity.  I have triple checked the gateway settings on the workstations, switches and the Cyberoam.  I have manipulated settings on the cyberoam and the Dell L3 switch where possible, but I have been unable to resolve this.  

I am assuming there is a setting/config in the L3 switch that I am not considering that is killing the incoming connection.  Does anyone have any ideas?
0
Comment
Question by:ntobin
  • 3
  • 2
6 Comments
 
LVL 39

Expert Comment

by:Aaron Tomosky
ID: 40439346
What ip addresses do workstations get? If they are not in that subnet, they have a different gateway. Each subnet/vlan will have its own gateway in that vlan.
0
 
LVL 1

Author Comment

by:ntobin
ID: 40439768
My logic was that the current firewall has an IP address of 10.1.0.254 /25 in VLAN 999, so I thought I could configure the new firewall with identical settings and have it "plug + Play" essentially.  

Is this not how it should work?
0
 
LVL 39

Expert Comment

by:Aaron Tomosky
ID: 40440198
It's part of how it should work. You need to identify ALL the subnets and gateway addresses for all the interfaces on the router. To exit a subnet, you go out the gateway for that subnet.
0
Who's Defending Your Organization from Threats?

Protecting against advanced threats requires an IT dream team – a well-oiled machine of people and solutions working together to defend your organization. Download our resource kit today to learn more about the tools you need to build you IT Dream Team!

 
LVL 2

Expert Comment

by:Dale McKay
ID: 40444894
Please post the Dell switch config
0
 
LVL 1

Accepted Solution

by:
ntobin earned 0 total points
ID: 40457868
Sorry for letting this hit the back burner, but we figured out what resolved this issue with the support of the firewall vendor.  
On a normal config we do not need to explicitly setup a static route , but because we have more than one vlan in this setup the firewall needed a static route that summarized all the subnets.  

So putting a static route of 10.0.0.0 /8 in the firewall resolved this.
0
 
LVL 1

Author Closing Comment

by:ntobin
ID: 40807601
Vendor resolved issue
0

Featured Post

Evaluating UTMs? Here's what you need to know!

Evaluating a UTM appliance and vendor can prove to be an overwhelming exercise.  How can you make sure that you're getting the security that your organization needs without breaking the bank? Check out our UTM Buyer's Guide for more information on what you should be looking for!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Is your computer hacked? learn how to detect and delete malware in your PC
This article will show you step-by-step instructions to build your own NTP CentOS server.  The network diagram shows the best practice to setup the NTP server farm for redundancy.  This article also serves as your NTP server documentation.
Get a first impression of how PRTG looks and learn how it works.   This video is a short introduction to PRTG, as an initial overview or as a quick start for new PRTG users.
NetCrunch network monitor is a highly extensive platform for network monitoring and alert generation. In this video you'll see a live demo of NetCrunch with most notable features explained in a walk-through manner. You'll also get to know the philos…

564 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