Got a wierd issue ..
We have done re-addressing of a subnet say 172.16.10.0/24 to a new IP range 10.x.x.x... everything works fine as expected. we defined 10.x.x.x as primary , and 172.16.10.x as secondary IP addresses on the VLAN, for migration purpose..
We have now migrated all IPs from 172.16.10.x to 10.x.x.x and wanted to delete the secondary IP range 172.16.10.0/24... Just before deleting, I wanted to make sure we dont have any Iive IPs on that segment. I looked on the core switch (show arp), and made sure there are no ARP associations for 172.16.10.x IPs..
Just to confirm, Im also doing a scan from my laptop (solarwinds ip scan), through a WAN connection, and strangely found some random IPs responding.. for eg i can ping 172.16.10.7 from my laptop from WAN, but not from LAN.. that IP never exists, but for some reason, im able to ping from my laptop in WAN. Can this be due to proxy arp on that vlan interface ? i have proxy arp enabled on the vlan SVI...
Will someone know the exact reason as to why IPs would not be reachable from LAN, and it responds randomly from WAN ? Can this be a bug ?
Note - there is no overlapping networks.. IPs are dedicated to that site.. when i do a tracert, it reaches the core switch of that site..