Ticket Options
Question Details
TICKET ARCHIVE -> Hostname Already Exists On Network.
techmanandy - Jun 14, 2005 - 1:19 pm
One of the employees at the company I support had tiger put on her Mac Laptop and sharing enabled on it. Ever since this happened, she has been getting an error message saying that the local hostname already exists on the network no matter what we change it to. I thought that the AirPort may be conflicting, but I disabled it and got the same message. I disabled automount, disabled sharing, and still the same message comes up over and over again about every 5 minutes or so. When I am in the network preferences for long enough, it will say another application has changed the preferences and none of the changes that I made were saved. Not quite sure what to do beyond this point. Thank you in advance.
macbri - Jun 16, 2005 - 7:51 am
Hi Andy -
Let's see if we can't figure out the problem. First of all, can you tell me how the laptop is configured for network? Does it obtain an IP address dynamically via DHCP or is it a static address? In either case, we'll have you find the IP address when the laptop is connected to the network. A quick way to get this information is to cut-and-paste the following command into a terminal:
ifconfig | grep inet | grep -v inet6
You will need access to another system on the network to continue. Disconnect the laptop from the network, and then try to "ping" the IP address your laptop has assigned to it:
/sbin/ping -c 3 xxx.xxx.xxx.xxx
Then try the same command again, only this time using your hostname instead of the ip address.
Let me know what information this gives us, and we'll continue from there!
- Brian
--------
Brian S. -- MacOSX.com Technical Support
Let's see if we can't figure out the problem. First of all, can you tell me how the laptop is configured for network? Does it obtain an IP address dynamically via DHCP or is it a static address? In either case, we'll have you find the IP address when the laptop is connected to the network. A quick way to get this information is to cut-and-paste the following command into a terminal:
ifconfig | grep inet | grep -v inet6
You will need access to another system on the network to continue. Disconnect the laptop from the network, and then try to "ping" the IP address your laptop has assigned to it:
/sbin/ping -c 3 xxx.xxx.xxx.xxx
Then try the same command again, only this time using your hostname instead of the ip address.
Let me know what information this gives us, and we'll continue from there!
- Brian
--------
Brian S. -- MacOSX.com Technical Support
techmanandy - Jun 16, 2005 - 1:52 pm
The results I got from the ifconfig were:
inet 127.0.0.1 netmask 0xff00000
inet 10.0.0.117 netmask 0xffffff00 broadcast 10.0.0.255
inet 10.0.0.116 netmask 0xffffff00 broadcast 10.0.0.255
The wierd thing is that all our other computers have a netmask of 255.0.0.0, but these two interfaces (an airport and a built in ethernet adapter) have subnet masks of 255.255.255.0.
I was not able to reach the hostname with the computer plugged in (from a Windows computer, we don't have another Mac available) but was able to reach the ip. This happens even with the airport disabled.
inet 127.0.0.1 netmask 0xff00000
inet 10.0.0.117 netmask 0xffffff00 broadcast 10.0.0.255
inet 10.0.0.116 netmask 0xffffff00 broadcast 10.0.0.255
The wierd thing is that all our other computers have a netmask of 255.0.0.0, but these two interfaces (an airport and a built in ethernet adapter) have subnet masks of 255.255.255.0.
I was not able to reach the hostname with the computer plugged in (from a Windows computer, we don't have another Mac available) but was able to reach the ip. This happens even with the airport disabled.
macbri - Jun 16, 2005 - 6:29 pm
hi Andy -
yes you're right, the private IP range 10.xxx.xxx.xxx would typically have a broadcast address of 255.0.0.0. So perhaps the network settings are incorrect or corrupted. So let's start with that: how is that IP address set up on the laptop? Is it dynamically assigned when you boot the system, or is it something you manually set up and that never changes?
Also, with the airport disabled *and* the network cable unplugged, can you still ping (from your windows box) the IP address(es) you reported? if so then another system on your network is using the IP address. Finding the culprit may require access to the network hardware to see where it's plugged in, and then working back to see where the machine physically resides.
If you *cannot* ping the IP address when your laptop is *totally* off the network, we may need to investigate further. Let me know what you find!
- Brian
--------
Brian S. -- MacOSX.com Technical Support
yes you're right, the private IP range 10.xxx.xxx.xxx would typically have a broadcast address of 255.0.0.0. So perhaps the network settings are incorrect or corrupted. So let's start with that: how is that IP address set up on the laptop? Is it dynamically assigned when you boot the system, or is it something you manually set up and that never changes?
Also, with the airport disabled *and* the network cable unplugged, can you still ping (from your windows box) the IP address(es) you reported? if so then another system on your network is using the IP address. Finding the culprit may require access to the network hardware to see where it's plugged in, and then working back to see where the machine physically resides.
If you *cannot* ping the IP address when your laptop is *totally* off the network, we may need to investigate further. Let me know what you find!
- Brian
--------
Brian S. -- MacOSX.com Technical Support
techmanandy - Jun 16, 2005 - 6:49 pm
It is dynamically assigned through DHCP from a Windows 2000 Server. I cannot ping the computer from the windows server when it is disconnected from the network (and the airport disabled). The wierd thing is, is that this message doesn't just come up once. It comes up, then the Mac updates the hostname (for example, if it was named MyComputer, it would update it to MyComputer-1), then keeps updating the hostname (increasing the numerical value at the end of the hostname). This seems to be happening at random. Sometimes it will happen in 5 minutes, sometimes it will take an hour. It can access all network services perfectly fine (HTTP, IMAP, FTP, etc). Hope this helps. By the way, I greatly appreciate the help.
macbri - Jun 17, 2005 - 7:39 pm
Hi Andy -
Just out of curiosity, is it possible to check your Windows 2000 DHCP server and see if it can exclude IPs from it's "pool" for assigning with DHCP? My idea is just to see what happens if you manually assign an IP address to the laptop. So for example, if you set the DHCP server to assign IPs in the range 10.0.0.2 to 10.0.0.254 and then assign an IP such as 10.1.1.1 to your laptop with the correct netmask as you noted (netmask 255.0.0.0, broadcasr 10.255.255.255). This is not a final solution mind you (unless you're happy wth it) but it might give us another clue or two on how to proceed!
Incidentally, it just ocurred to me that you might cancel and re-issue the DHCP lease for your laptop on the DHCP server, and see if that resolves the incorrect netmask problem? Both suggestions are really an attempt to see what happens when the laptop has the correct IP/netmask settings.
- Brian
--------
Brian S. -- MacOSX.com Technical Support
Just out of curiosity, is it possible to check your Windows 2000 DHCP server and see if it can exclude IPs from it's "pool" for assigning with DHCP? My idea is just to see what happens if you manually assign an IP address to the laptop. So for example, if you set the DHCP server to assign IPs in the range 10.0.0.2 to 10.0.0.254 and then assign an IP such as 10.1.1.1 to your laptop with the correct netmask as you noted (netmask 255.0.0.0, broadcasr 10.255.255.255). This is not a final solution mind you (unless you're happy wth it) but it might give us another clue or two on how to proceed!
Incidentally, it just ocurred to me that you might cancel and re-issue the DHCP lease for your laptop on the DHCP server, and see if that resolves the incorrect netmask problem? Both suggestions are really an attempt to see what happens when the laptop has the correct IP/netmask settings.
- Brian
--------
Brian S. -- MacOSX.com Technical Support
IF THIS IS YOUR QUESTION AND YOU WISH TO RESPOND, LOGIN HERE FIRST.
