ee70dcc8   
   From: mdw@distorted.org.uk   
      
   SpreadTooThin  writes:   
      
   > If a computer is rebooted and you issue an arp request the host you   
   > are looking for in the arp table may not be there.  (Correct?)   
      
   If, by `issue an arp request', you mean `run arp(8) or similar' to   
   inspect the ARP cache, then yes.  Otherwise I'm afraid I don't   
   understand what you mean.   
      
   > However if you do a ping of that host then do the arp the host is very   
   > likely to be in the arp table.  (Am I correct?)   
      
   You are indeed.   
      
   > So is there any other simple network operation you can perform so that   
   > you can be sure the host is in the arp table when you issue the arp   
   > command?   
      
   To populate the ARP cache, you need to exercise the IP stack's IP packet   
   sending machinery.  Usually this involves actually sending a packet.   
   The ping(8) program produces pretty innocent packets, so should be all   
   right; if you don't want to start an external program, and either want   
   to run unprivileged (I don't blame you) or just find the thought of   
   messing with raw sockets unpleasant (I don't blame you for that either!)   
   then sending UDP to port 9 ought to do the job.  (Port 9 is the   
   `discard' port -- with a little luck, the recipient will silently ignore   
   your packet.)   
      
   -- [mdw]   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)