I have a client with a small network.
Their DHCP is handled by their SBS 2011 server, their are two Belkin wireless devices set up as access points, and there is one tp-link un-managed switch. Other than that there is a Linksys firewall device (gateway) between their network and a cable modem.
The issue is that occasionally two specific workstations will drop off the network and I will find their IP addresses to be on the 192.168.99.x range, instead of the 192.168.100.x range. When I look at the network connection on the affected workstations, instead of seeing their domain name in the connection I see 'innotech.com'. This makes no sense to me since no one knows of any other hardware in the building. When the computer get's it's lease from the 192.168.99.x range, it cannot access the resources on their network and I can connect to a gateway on '192.168.99.1' over http and I receive a login prompt, which none of their documented passwords work with.
What should I do? How can I find out what device is giving these workstations DHCP leases on the 192.168.99.x range.
Best Answer +BudMan , 28 August 2013 - 16:04
Good news! But having a smart switch would of allowed you to figure out which port it was without having to walk around the building and trace a wire.
Might be something to look into for making your network better.. They are not very costly, give you lots of troubleshooting tools, ability to vlan in the future, rate control of connections quite likely.
Not saying you need a full managed switch like a 2k$ cisco - but a $200 smart makes a lot of sense in a small office vs just a simple dumb switch you would run in your house with a few connections. Go to the full post