Most of these services monitor a specific port as shown in
NETSTAT *CNN
On the NETSTAT *CNN if you do "F14=Display port numbers" you can see the
numbers.
Too bad NETSTAT *CNN doesn't have an *OUTFILE option. As an alternative
you could try using this API:
List Network Connections (QtocLstNetCnn)
http://www-01.ibm.com/support/knowledgecenter/ssw_ibm_i_72/apis/qtoclstnetcnn.htm?lang=en-us
To list them out to some file.
Then a remote client could attempt a remote command, to generate the list,
followed by a download, and then look for ports you are interested in. If
the ports not listed then the port is down.
If you had multiple lpars you could monitor each other. You could even go
so far as the sockets programs by Scott Klement to test the various ports
for listeners.
IBM has a product, called EDGE. We use that as a smart router. For
example if you go to our intranet site of dekkohome.corp.dekko.com it
looks for port 80 serviced by one IP address on one lpar. If that port is
down then it goes to port 80 on another lP address served up by another
lpar and so on. You can either do it this way or load balancing between
all active port 80's on a list of IP addresses. I've not played with it
to see if it has notifications if a certain port on a certain IP address
is down.
You can also google port testing software and you'll get a bunch of hits,
including some free downloads.
Rob Berendt
midrange.com
