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Host Names Showing 1 Name On All Devices
I really hope someone can help with this issue. It is strange. I did a network scan on one of my LAN's in the field and all the devices came up with the same Host Name. For instance, each computer has its own distinct name, but on the scan, it shows several computers having one of 3 different host names. I know this is not set up in the computers because I did an individual name check on each computer. No matter what I use to scan the devices - Advanced IP Scanner, SolarWinds IPAM Summary, and even my Malwarebytes network scan. I have no idea how to remedy this issue or how it came to be.
This Lan is on its own router, using its own Fiber Circuit. It uses a VPN tunnel to connect to the headquarters site just for authentication purposes.
Are there any suggestions.
This Lan is on its own router, using its own Fiber Circuit. It uses a VPN tunnel to connect to the headquarters site just for authentication purposes.
Are there any suggestions.
ASKER
I am scanning based on IP range. For instance I will scan the network for 10.100.84.x and will get IP results from 100 devices (this site has 30 at the most). The results show IP address, Host name and logged on user. All the host names are 1 of three names. For instance I see 10 devices with the name Paddlegirl. The Scan software I am using shows me if the IP is attached to a logged in device and I can see it is a computer or printer. Three of these 10 devices are printers. I can remote into the printer and see the actual correct Host name and it is not Paddlegirl.
what does nslookup on the network adress show?
In the case you see the name multiple times: you need to correct DNS for reverse lookups.
In the case you see the name multiple times: you need to correct DNS for reverse lookups.
ASKER
I see the same hostnames that are showing up in my scans.
The you most probably need to fix the reverse lookup entries....
(zone: arpa, in-addr, .... ip address / part. and it should contain PTR records).
1.84.100.10.in-addr.arpa. PTR somename.your.localdomain.
(zone: arpa, in-addr, .... ip address / part. and it should contain PTR records).
1.84.100.10.in-addr.arpa. PTR somename.your.localdomain.
ASKER
Okay. I am looking at this and everything is set up correct as your example, but mine look like this PTR mssd10109.ccps.local (this is not even my domain, so I don't know where this came from; the others at least have our local domain correct). I have 16 others LANs and they are all correct.
Tip: Be sure you consider point from which you're initiating a scan.
For example, your LAN... say a residential ISP connection running many devices...
Also how you have DNS configured internally.
1) Scanning inside your LAN will show all your local IP addresses.
2) Scanning outside your LAN will show only a single IP address from your incoming ISP.
3) Any device names showing up will depend on how you've setup your local DNS.
Note: Device name != DNS lookup name.
Very few scanners have any awareness of device names, because device naming is implemented differently on different OS types.
For example, your LAN... say a residential ISP connection running many devices...
Also how you have DNS configured internally.
1) Scanning inside your LAN will show all your local IP addresses.
2) Scanning outside your LAN will show only a single IP address from your incoming ISP.
3) Any device names showing up will depend on how you've setup your local DNS.
Note: Device name != DNS lookup name.
Very few scanners have any awareness of device names, because device naming is implemented differently on different OS types.
ASKER
I have 16 different Lans and I am scanning from our Headquarters which is not a part of the particular LAN. All of them are set up the same as well as the local DNS. The Host Names that are showing up are fictitious and are not names of anything on my Lan. It is confusing to see several devices with the same Host Name.
ASKER
I was looking at my DNS Reverse lookup settings again. I did notice that I saw this across my others Lans also, not to the same magnitude, but enough that I took notice. I looked at the properties and saw that the Name Server had a device listed that was no longer in use. I took it out and left the appropriate DNS server. I don't know if this will fix issue, but I will let you know.
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ASKER
Thank you for all your suggestions. I didn't realize old PTR records would show up in scans.
Scan will just try to find a name with a number...., your DNS will provide a name if it can...
THe real problem is that devices that get turned off, don;t remove stale records.
The solution would probably be that only the DHCP server may update DNS, then the DHCP server will remove stale records when leases terminate.
THe real problem is that devices that get turned off, don;t remove stale records.
The solution would probably be that only the DHCP server may update DNS, then the DHCP server will remove stale records when leases terminate.
Are you in a position to provide the names you pick when you scan your network? I have a feeling that these scanners might be showing you NIC Manufacturer names, or chipset names. When you try to ping your fellow computers from within the network, does the name resolve to their IP? Are the IPs the same, or different? Which switch are you using to connect the computers?