I have started a new company with little documentation on the lan and wan, is there any software snmp or such that can pull all the info from my devices and map out the network effectively doing a drawing, with interface ip's etc ?
It uses snmp. Displays physical layout and detailed logical views of the network, including Layer 2/3, OSPF, EIGRP, MPLS, PVCs, VLANs, VPNs, BGP, HSRP/VRRP, and device virtualization. Quite complex diagram, that includes interfaces, vlans , IPs, Equipment type, etc.
First of all I have never found a tool that is very very good at this. it might be because of the complexity needed..
The only freeware I know of is Cheops-ng and that is a product that have been down for many years I think. (man I am getting old)
Checkout Solarwinds LANSurveyor or the Engineer toolkit.
What I do to begin with if I where in your shoes is basically follow the route.
Start with the routers/firewalls and follow them, write it down and then i go with the VLAN´s follow them and check where they go.
then down to L2 and check out what the switches are up to.
while you are there (in the routers/switches/firewalls) make a backup of all the information (license keys/config and so on) if you do not have one..