Figuring out the ntp(date) check

Hi,

I was trying to figure out, how the ntp-check works, as I sometimes get a "no server suitable for synchronization" error when performing this check.

Im not much of a C-coder, so I have why this line is triggered in the code from bbtest-net.c below:

void run_ntp_service(service_t *service) { testitem_t *t; char cmd[1024]; char *p; char cmdpath[PATH_MAX];

    p = xgetenv("NTPDATE");
    strcpy(cmdpath, (p ? p : "ntpdate"));
    for (t=service->items; (t); t = t->next) {
            if (!t->host->dnserror) {
                    sprintf(cmd, "%s -u -q -p 2 %s 2>&1", cmdpath, ip_to_test(t->host));
                    t->open = (run_command(cmd, "no server suitable for synchronization", t->banner, 1, extcmdtimeout) == 0);
            }
    }

}

Can anyone explain under what conditions that phrase occurs?

Regards,

Carl Melgaard