| Parent | pass | NS records at parent servers | Your NS records at the parent servers are: e.twnic.net.tw. [ 211.20.231.12 ] f.twnic.net.tw. [ 220.229.225.196 ] g.twnic.net.tw. [ 203.119.3.2 ] h.twnic.net.tw. [ 203.119.3.2 ] a.twnic.net.tw. [ 192.83.166.9 ] b.twnic.net.tw. [ 203.73.24.203 ] c.twnic.net.tw. [ 168.95.192.10 ] d.twnic.net.tw. [ 210.17.9.229 ] [These were obtained from c.dns.tw.] |
| pass | Glue at parent nameservers | Parent nameservers (I checked with c.dns.tw.) know A record for your domain, Very good ! | |
| NS | info | NS records at your nameservers | Your NS records at your nameservers are: 211.20.231.12 Lame nameserver 220.229.225.196 Lame nameserver 203.119.3.2 Lame nameserver 203.119.3.2 Lame nameserver 192.83.166.9 Lame nameserver 203.73.24.203 Lame nameserver 168.95.192.10 Lame nameserver 210.17.9.229 Lame nameserver |
| pass | Mismatched glue | OK. The DNS report did not detect any discrepancies between the glue provided by the parent servers and that provided by your authoritative DNS servers. | |
| pass | No NS A records at nameservers | OK. Your nameservers do include corresponding A records when asked for your NS records. This ensures that your DNS servers know the A records corresponding to all your NS records. | |
| fail | All nameservers report identical NS records | ERROR. The NS records at all your nameservers are different, check the info above for details. | |
| pass | All nameservers respond | OK. All of your nameservers listed at the parent nameservers responded. | |
| pass | Nameserver name validity | OK. All of the NS records that your nameservers report seem valid (no IPs or partial domain names). | |
| pass | Number of nameservers | OK. You have 8 nameservers. You must have at least 2 nameservers (RFC2182 section 5 recommends at least 3 nameservers), and preferably no more than 7. | |
| fail | Lame nameservers | ERROR: lame nameservers: e.twnic.net.tw. [211.20.231.12] f.twnic.net.tw. [220.229.225.196] g.twnic.net.tw. [203.119.3.2] h.twnic.net.tw. [203.119.3.2] a.twnic.net.tw. [192.83.166.9] b.twnic.net.tw. [203.73.24.203] c.twnic.net.tw. [168.95.192.10] d.twnic.net.tw. [210.17.9.229] | |
| pass | Missing (stealth) nameservers | OK. All 2 of your nameservers (as reported by your nameservers) are also listed at the parent servers. | |
| pass | Missing nameservers 2 | OK. All of the nameservers listed at the parent nameservers are also listed as NS records at your nameservers. | |
| pass | Nameservers on separate class C's | Your nameservers seems to be in different networks. | |
| pass | All NS IPs public | OK. All of your NS records appear to use public IPs. If there were any private IPs, they would not be reachable, causing DNS delays. | |
| SOA | info | SOA record | Your SOA record is: Primary nameserver: Hostmaster E-mail address: Serial #: Refresh: Retry: Expire: Default TTL: |
| pass | NS agreement on SOA Serial # | OK. All your nameservers agree that your SOA serial number is . That means that all your nameservers are using the same data. | |
| fail | SOA MNAME Check | ERROR: Your SOA (Start of Authority) record states that your master (primary) name server is: That server is not listed at the parent servers, which is not correct. | |
| warn | SOA Serial Number | Your SOA serial number is: . This not appears to be in the recommended format of YYYYMMDDnn, where 'nn' is the revision. This number must be incremented every time you make a DNS change. | |
| warn | SOA REFRESH value | Your SOA REFRESH interval is : seconds. This seems too small (about 3600-7200 seconds is good if not using DNS NOTIFY; RFC1912 2.2 recommends a value between 1200 to 43200 seconds (20 minutes to 12 hours)). This value determines how often secondary/slave nameservers check with the master for updates. | |
| warn | SOA RETRY value | Your SOA RETRY interval is : seconds. This seems too small (about 120-7200 seconds is good). The retry value is the amount of time your secondary/slave nameservers will wait to contact the master nameserver again if the last attempt failed. | |
| warn | SOA EXPIRE value | Your SOA EXPIRE time is : seconds. This seems too small (about 1209600 to 2419200 seconds (2-4 weeks) is good). RFC1912 suggests 2-4 weeks. This is how long a secondary/slave nameserver will wait before considering its DNS data stale if it can't reach the primary nameserver. | |
| warn | SOA MINIMUM TTL value | Your SOA MINIMUM TTL is : seconds. This seems too small (about 3,600 to 86400 seconds or 1-24 hours is good). RFC2308 suggests a value of 1-3 hours. This value used to determine the default (technically, minimum) TTL (time-to-live) for DNS entries, but now is used for negative caching. | |