nanog mailing list archives
Re: large organization nameservers sending icmp packets to dns servers.
From: Valdis.Kletnieks () vt edu
Date: Mon, 06 Aug 2007 11:57:08 -0400
On Mon, 06 Aug 2007 11:53:15 EDT, Drew Weaver said:
Is it a fairly normal practice for large companies such as Yahoo! And Mozilla to send icmp/ping packets to DNS servers? If so, why?
Sounds like one of the global-scale load balancers - when you do a (presumably) recursive DNS lookup of one of their hosts, they'll ping the nameserver from several locations and see which one gets an answer the fastest. Yes, it's a semi-borkken strategy, because it assumes that: 1) ICMP is handled at the same rate as TCP/UDP packets in all the routers involved (so there's no danger of declaring a path "slow" when it really isn't, just becase a router slow-pathed ICMP). 2) That the actual requester of service is reasonably near net-wise to the server handling the end-user's recursive DNS lookup.
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Current thread:
- large organization nameservers sending icmp packets to dns servers. Drew Weaver (Aug 06)
- Re: large organization nameservers sending icmp packets to dns servers. Valdis . Kletnieks (Aug 06)
- Re: large organization nameservers sending icmp packets to dns servers. Steven M. Bellovin (Aug 06)
- Re: large organization nameservers sending icmp packets to dns servers. John Levine (Aug 06)
- Re: large organization nameservers sending icmp packets to dns servers. Valdis . Kletnieks (Aug 06)
- Re: large organization nameservers sending icmp packets to dns servers. John L (Aug 06)
- Re: large organization nameservers sending icmp packets to dns servers. Patrick W. Gilmore (Aug 06)
- Re: large organization nameservers sending icmp packets to dns servers. Chris L. Morrow (Aug 06)
- Re: large organization nameservers sending icmp packets to dns servers. Peter Dambier (Aug 06)
- Re: large organization nameservers sending icmp packets to dns servers. Joe Abley (Aug 06)
- Re: large organization nameservers sending icmp packets to dns servers. Steven M. Bellovin (Aug 06)
- Re: large organization nameservers sending icmp packets to dns servers. Valdis . Kletnieks (Aug 06)
- RE: large organization nameservers sending icmp packets to dns servers. Jason J. W. Williams (Aug 07)
- RE: large organization nameservers sending icmp packets to dns servers. Donald Stahl (Aug 07)