I know this one is a tricky one because the problem could potentially be caused by quite a few different things. However maybe you've come across something similar or have some hints or tips of how I may be successful in debugging the current setup.
Basically we are running a small/medium sized office network with the current setup:
- Load balancer (Draytek Vigor 3300)
- Inside the load balancer we have 2 Cisco managed switches
- The load balancer is connected to 3 routes which supply the connection to the internet.
The problem is that every now and then the network(LAN and External) either slows down considerably, or the LAN is fine but external traffic comes to a complete standstill. This doesn't even occur in set intervals, we sometimes go weeks without noticing any problems. Restarting the load balancer solves the issue until the next time it happens.
Now, I appreciate that this is near impossible to solve without actually looking at the setup however I thought that maybe someone had been in a similar situation before or has any ideas what the problem might be.
If you need any more information please let me know