On Mon, Dec 18, 2000 at 01:12:17AM -0800, Matt Levine wrote:
Well, although there's no entirely fool-proof way, We've found a better way of monitoring "real" outages/issues is to monitor the time required to setup a tcp connection to some "trusted" machines. For example, in our VA datacenter we monitor the time required to setup a connection with tier1 providers (UU,BBN,DIGEX for example) nameservers (on port 53).. We've found it slightly more reliable than ICMP reqs, especially since when routers get busy, it shows as degradation vs. outage.
How does your "DNS ping" work, do you just open and close a TCP connection? Or make actual requests? Like, "dig soa provider.net @ns.provider.net". But perhaps if everyone starts doing this to the same box, it could be seen as DoS? -- http://www.internet.org.ph Internet and ISP's in the Philippines http://www.ASARproject.org Artists for Social Action and Response GSM Mobile: +63-917-810-9728