Why Is A Ping Close To Useless?
Depends on what you want to do.
If you simply want to check the network card, then a Ping is fine, as checking the network card is all a Ping does.
First, some background.
The transport protocol Argent uses is called TCP/IP, as the letters suggest it is actually a combination of two protocols. TCP/IP delivers packets of data from one physical network device to another.
In the case of a server, this ‘device’ is the network card or NIC (Network Interface Controller).
Once the NIC has received the packet and done some simple checking – and not much is checked at this physical layer – then the packet is hopefully passed up to the server.
Now there’s the rub…
For a NIC card to be happy, all it needs is power from the server’s motherboard and a connection to the Internet.
It does not care — and does not know — about the health of its mother server.
A Windows server could have a blue screen, and the NIC is still as happy as a clam.
Now you see the limitations of the humble Ping – the Ping just checks the NIC card is alive, not the server.
So what is a better approach?
Actually there are a number of better approaches.
Of course Argent provides all these options to you – you can select the one that is most appropriate for the particular server.
Here are your choices:
Check The Existence Of A File On The Server
This is the best test of all because it exercises many of the critical components of the actual operating system itself – the disk subsystem, the file system, as well as process creation. Thus the overall heath of the complete operating system is checked. A far cry from the humble physical-level NIC card getting a TCP/IP packet attached to a Windows server with a blue screen.
Call The TOD API
The Time Of Day (TOD) API is one of the slowest and one of the most expensive – in terms of CPU cycles – of all the Windows APIs. The reasoning of using this test is: if the TOD API is running, we can assume the rest of the APIs are running as well.