 | vbseo.com | |||
 | ns1.crawlability.com | 75.126.140.204 | ||
 | ns2.crawlability.com | 75.126.140.205 | ||
| vbseo.com | |||
| ns1.crawlability.com | 75.126.140.204 | ||
| ns2.crawlability.com | 75.126.140.205 | ||
IP addresses are likely to be all on the same subnetTo avoid losing all connectivity with the authoritative DNS in case of network outage it is advised to host the DNS on different networks.
The Domain Name System requires that multiple servers exist for every delegated domain (zone). This document discusses the selection of secondary servers for DNS zones. Both the physical and topological location of each server are material considerations when selecting secondary servers. The number of servers appropriate for a zone is also discussed, and some general secondary server maintenance issues considered.
All the servers are likely to be on the subnet 75.126.140.192/28, try moving some of them to another subnet.
Nameservers are all part of the same ASTo avoid losing all connectivity with the authoritative DNS in case of a routing problem inside your Autonomous System, it is advised to host the DNS on different AS.
All the nameservers are part of the same Autonomous System (AS number 36351), try to have some of them hosted on another AS.
Reverse for the nameserver IP address doesn't match
The hostmaster can't be contacted by emailUnable to send email to the hostmaster address (dev@crawlability.com) using relays: aspmx.l.google.com, alt1.aspmx.l.google.com, alt2.aspmx.l.google.com, aspmx2.googlemail.com, aspmx3.googlemail.com.
