Timothy Murphy wrote: > Ljubomir Ljubojevic wrote: > >>> (1) I can open port 22 on the Billion, allowing me to ssh in from >>> outside. But for some reason I cannot ping the same address from >>> outside. > >> This is due to modem refuses to answer to pings. You might have option >> to allow it in modem config. >> >> Ping (ICMP) does not use ports but it is packet of type 8. > > Thanks again for your response. > Could CentOS be preventing me from pinging the system?
Further to my question, how can I determine if it is the Billion 5200S modem/router that is preventing pings, or if it is the CentOS-6 MicroServer attached to the modem/router? I don't see any reference to ICMP on the modem web-page. On the other hand the CentOS firewall seems to allow ICMP unless explicitly rejected (which I haven't done). Surely it would be slightly odd for a modem/router to reject pings by default? Is there any simple way, short of using something like ethereal, of determining if ICMP packets are reaching the computer, and being rejected there? -- Timothy Murphy e-mail: gayleard /at/ eircom.net tel: +353-86-2336090, +353-1-2842366 s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
