Ok… here is what I get for Time to Lookup for one domain that appears fine:
Time to look up myitanalyst.com A record
Generated by www.DNSstuff.com at 15:48:00 GMT on 30 Sep 2005.
Searching for myitanalyst.com A record at a.root-servers.net Got referral to F.GTLD-SERVERS.NET. [took 7 ms]
Searching for myitanalyst.com A record at F.GTLD-SERVERS.NET. Got referral to ns2.starcityhosting.net. [took 71 ms]
Searching for myitanalyst.com A record at ns2.starcityhosting.net. Reports an answer.
Record is:
Domain Type Class TTL Answer
myitanalyst.com. A IN 86400 204.14.108.240
myitanalyst.com. NS IN 86400 ns1.starcityhosting.net.
myitanalyst.com. NS IN 86400 ns2.starcityhosting.net.
ns1.starcityhosting.net. A IN 86400 204.14.104.105
ns2.starcityhosting.net. A IN 86400 204.14.106.14
Looking up at ns1.starcityhosting.net… Reports 1 A record(s). 33ms.
Looking up at ns2.starcityhosting.net… Reports 1 A record(s). 31ms.
Average of all 2 nameservers: 32ms (plus 78ms overhead).
Score: A
Took off 2 points since ns1.starcityhosting.net allows recursive lookups (if lots of people are using the server, it can slow down).
Took off 2 points since ns2.starcityhosting.net allows recursive lookups (if lots of people are using the server, it can slow down).
Note: The 78ms overhead is the time it takes to get your NS records from the parent servers, and indicates a worst-case scenario (normally, the resolving DNS server would have the common parent server entries cached, and would know the parent server(s) that were responding most quickly). The best times since the last time this web server was last restarted are: 3ms average response, plus 11ms overhead. Note that these times are from a server located in the United States; if most of the people using your DNS are outside of the United States, your actual results may be better than what is shown here. A rating of ‘B’ or higher is generally good (this tool is very picky!). This tool is designed to make an educated guess about speed, and to point out potential factors that may reduce the DNS speed, and it is not perfect.
AND here is what I get for a second domain that shows as an F grade. The main difference is it is on NS3 and NS4 instead of NS1 and NS2:
Time to look up fellowshipmissions.info A record
Generated by www.DNSstuff.com at 16:43:53 GMT on 30 Sep 2005.
Searching for fellowshipmissions.info A record at d.root-servers.net Got referral to TLD4.ULTRADNS.ORG. [took 5 ms]
Searching for fellowshipmissions.info A record at TLD4.ULTRADNS.ORG. Got referral to ns4.starcityhosting.net. [took 12 ms]
[Had to look up A record for ns4.starcityhosting.net.; assume 200ms]
Searching for fellowshipmissions.info A record at ns4.starcityhosting.net. Reports an answer.
Record is:
Domain Type Class TTL Answer
fellowshipmissions.info. A IN 86400 204.14.108.240
fellowshipmissions.info. NS IN 86400 ns4.starcityhosting.net.
fellowshipmissions.info. NS IN 86400 ns3.starcityhosting.net.
ns4.starcityhosting.net. A IN 156148 204.10.105.200
Looking up at ns4.starcityhosting.net… [Had to look up A record for ns4.starcityhosting.net; assume +200ms]…Reports 1 A record(s). 234ms.
Looking up at ns3.starcityhosting.net… [Had to look up A record for ns3.starcityhosting.net; assume +200ms]…Reports 1 A record(s). 273ms.
Average of all 2 nameservers: 253ms (plus 217ms overhead).
Score: F
Took off 8 points for “.info” TLD (extra lookups likely will be necessary to find the parent servers).
Took off 8 points for having no glue at a parent server [adds 2 extra packets to lookup].
Took off 6 points for having no glue for ns4.starcityhosting.net [adds 2 extra packets to lookup].
Took off 2 points since ns4.starcityhosting.net allows recursive lookups (if lots of people are using the server, it can slow down).
Took off 6 points for having no glue for ns3.starcityhosting.net [adds 2 extra packets to lookup].
Took off 2 points since ns3.starcityhosting.net allows recursive lookups (if lots of people are using the server, it can slow down).
Took off 20 points for >200ms average response time.
Note: The 217ms overhead is the time it takes to get your NS records from the parent servers, and indicates a worst-case scenario (normally, the resolving DNS server would have the common parent server entries cached, and would know the parent server(s) that were responding most quickly). The best times since the last time this web server was last restarted are: 3ms average response, plus 11ms overhead. Note that these times are from a server located in the United States; if most of the people using your DNS are outside of the United States, your actual results may be better than what is shown here. A rating of ‘B’ or higher is generally good (this tool is very picky!). This tool is designed to make an educated guess about speed, and to point out potential factors that may reduce the DNS speed, and it is not perfect.
Note: If your results seem poor, it is most likely due to the ‘no glue’ issue. Do not blame your DNS hosting company. If you change your NS records to be ones on the .info TLD, it will fix this problem. This problem only affects the speed of initial DNS lookups on your domain.
You can always go to DNSStuff.com and see it live.
Could someone shed some light on this? Thanks