Hi ! I need to use the InetAddress.isReachable() function to check some hosts. This function's implementation tries first to execute an ICMP ping if it has enough rights and if not, performs a TCP ping on port 7. Right needed for ICMP is Suid (given by chmod +s) and root execution.
I have a test class in a Jar which does this job very well if I execute the jar file as root and if I have launched a chmod +s on it. But if I try to launch it with JSVC, the class is unable to perform ICMP pings (I am sure because TCP are stopped by a firewall). I have made a chmod +s on : - jsvc - java - the jar JSVC is launched as root. I know all that is bad, but ... anyway for the moment ! For information, I don't want to use the "ping" command of the OS because I will have to performs thousands of ping every 3mn and I am afraid the OS command will increase the RAM load too high ... So I suppose the isReachable implementation is less resources consuming. May be I am wrong :-) I don't know what do to do now ! It would be great if anybody has any idea ... Best regards, Sylvain Caillet
