I somehow configured my Mac to route all requests for a particular IP Name (sample.com) to the loopback address ( Now I'm trying to remove this, but can't determine where to do it.

  1. There is no entry for it under /etc/hosts.
  2. The routing table shows that it is mapping the IP Name to the IP address of the Mac.

Routing table output below:


Destination        Gateway            Flags    Refs      Use  Netif Expire
default          UGSc        4        1    en0
127                sample.com         UCS         0        0    lo0
sample.com         sample.com         UH          1     7093    lo0
169.254            link#4             UCS         0        0    en0
192.168.2          link#4             UCS         6        0    en0        0:11:22:22:3f:fa   UHLW       20    55565    en0   1070       tsema.org          UHS         0        9    lo0      link#4             UHLWb       4    84777    en0

Any help would be greatly appreciated!

Update: Note - I can delete the route to the address - just not the loopback. I'm guessing that it needs to be removed someplace else...


So the key seems to have been that this is a host alias.

  1. I found a useful post

  2. I checked the cache for hosts

    sudo dscacheutil -cachedump -entries Host

  3. I found the host alias listed under /Local/Default

  4. I checked the Directory Services:

    sudo dscl localhost -list Local/Default/Host

  5. Sure enough, there it was!

  6. I deleted it:

    sudo dscl localhost -delete Local/Default/Hosts/sample.com

At some point we'll see if it remains gone following a reboot, but for now, the problem has been solved!


You may also try to flush the routing tables!

# cf. http://ola-bini.blogspot.com/2008/05/faulty-routes-on-macos-x.html
sudo route flush

To delete a specific route use:

sudo route delete <ipnum>

To get the default route use:

route -n get default
netstat -rnf inet  # ... and compare it with the Routing tables

As a last resort replace the contents of your current /etc/hosts file with its original contents below and reboot your computer.

# original /etc/hosts on Mac OS X 10.6
# Host Database
# localhost is used to configure the loopback interface
# when the system is booting.  Do not change this entry.
##   localhost broadcasthost
::1             localhost 
fe80::1%lo0 localhost

Execute the following in the terminal: route delete sample.com

  • 1
    That errs: route: writing to routing socket: No such process delete host sample.com: not in table – user40853 Apr 17 '10 at 21:25

As mentioned in the useful post you found, OS X now reads /etc/hosts like every other OS out there, so there's no need to invoke the Cthulhoid horror of NetInfo any more.

  • Right! And although it's a bit cloudy, I'm pretty sure that it was during the OSX 10.4 days that I was forced to use NetInfo to get the entry in there. Cthulhoid, indeed :) – user40853 Apr 17 '10 at 23:14

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