On 20/10/18 at 03:55, Steve Litt wrote: [...]
> Stop the madness! 👍 [...] > http://smarden.org/runit/runscripts.htm This link is http://smarden.org/runit/runscripts.html actually. > ======================================================= > #!/bin/sh > if ping -4 -c1 8.8.8.8 > /dev/null; then > (/etc/unbound/primecache.sh &) > exec unbound -dp > else > sleep 1 > fi > ======================================================= I am one of those who scoffes when he sees a ping to some Internet site to test the availability of network connectivity. There are dozens of ways this ping could fail beyond being the networking interface not setup correctly, among the possibilities: the site being off-line, some router between your box and the specific site malfunctioning, some firewall filtering ICMP echo-* packets, excessive lag that makes the pings timeout. It's also a time-consuming way to test for connectivity. Besides, I don't want to let Google know when I switch my box on and how often do I reconfigure my networking. Pinging the default gateway is better: GW=$(ip route list | sed -rn 's/^default via ([0-9a-f:.]+) .*/\1/p') ping -c 1 "$GW" You could also use ip route list | awk '($1 == "default") {print $3}', but I figured out awk is considerably slower than sed, 40% slower in this case. Still, this probe too could fail, because if the gateway is some box outside your control (ie is some apparatus your ISP is in control of) it too could be firewalled or temporarily off-line (some ISP take a handful of seconds before you can actually use your default gateway to navigate the Internet). In my opinion when one tests for Internet connectivity one should only test for some interface being ON and a default gateway being configured and stop there. If these two conditions are met, any further issue goes beyond interface configuration and must be investigated separately, leaving all your local services go ahead starting and configuring themselves like they should when your local interface goes up successfully. Alessandro -- Alessandro Selli <alessandrose...@linux.com> VOIP SIP: dhatarat...@ekiga.net Chiave firma e cifratura PGP/GPG signing and encoding key: BA651E4050DDFC31E17384BABCE7BD1A1B0DF2AE
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