Slow / No internet issues

[OceanicNomad]

Hi all,

I am at a loss after trying to search and figure this out myself. I have taken over a network which is over complicated and recently changed out a switch that failed with a like for like swap. I had a copy of the run config and I uploaded it and got the majority of the network talking again. I however now have no or extremely slow and intermittent internet on my end clients be it WiFi or Hardwired.

The internet does work when I manually change the client proxy settings to use that of the firewall (Kerio NG510), bare in mind I have not changed any other settings in the network apart from configuring the new 2960 with the original run config of the dead unit.

Basic topography:

Basic Topography

So to explain this, the Kerio NG510 is a firewall which allows multiple WAN's to be connected and routed to various VLAN's (IP groups). Currently there is one WAN connected and all traffic rules point to this WAN.

The Cisco 2921 is acting as the DHCP server and the Cisco SIP CME, the rest of the switches just have devices connected on their respective VLAN's with the C9200L being the switch for the 17 AP's connected to the WLC.

Now as I mentioned, when I connect any client to any VLAN network, either on WiFi or Hardwired I have extremely slow, sometimes no connection when browsing the web. Kerio NG510 has a non transparent proxy, which when used on the client allows perfect internet connection.

I have added the config files (redacted slightly) for the 2960 and the router. Any help would be greatly appreciated.

[Flavio Miranda · Accepted solution]

@OceanicNomad 

I would suggest to not use two default routes on the router

!
ip route 0.0.0.0 0.0.0.0 10.10.10.1
ip route 0.0.0.0 0.0.0.0 GigabitEthernet0/1
!

But, I dont see anything on the router or switch that could cause/explain internet issue.

 What If you connect one of your links to your router for test purpose? The problem can be on the firewall or on ISP.

[OceanicNomad]

@Flavio Miranda Thank you for responding as so quickly too. I completely missed this and did not even think it would be causing the issues. Turns out that they both point to the firewall but one was static 10.10.10.1 and the other was 10.10.10.2, looping back to the router. Removing the interface static route fixed the issue.