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Application connects only after Ping test...

I have quite a strange situation happening. We have a remote administration application that connects to a server via IP, the connection will not happen and I get a "Server Not Found" error message anytime I try to launch the app. However, if I will first ping the host, which the host replies successfully, then try and launch the app, the connection happens...

Any ideas????

  • Other Network Infrastructure Subjects

Re: Application connects only after Ping test...

Before u do the ping, can u check to see if there's already a mac-address resolution to the IP u're connecting to?

And when u launch ur application, and when it fails, can u also check n see if a mac-address resolution to the IP is already in the arp cache of ur host?

What i think is, when u do a ping, it checks its arp cache and not find an entry for the destination ip, hence does an arp for the mac. Once resolved the dst. IP to mac, ur application then knows how to connect to it.

Somehow, in any normal circumstance, the launching of any application will arp for the dst. host mac if the local host does not already have an arp entry for the dst. ip.

If ur dst. ip is located in a different network crossing a gateway, the local host should then arp for the gateway's mac.