HTTP Header reponses of 37signals.com is the information we get when HTTP request sent to a server from connecting clients(e.g. chrome, firefox). When you input an address into your browser it sends a request to the server hosting the domain and the server responds. HTTP Header information is not directly displayed by normal web browsers like chrome, firefox etc.
HTTP/1.1 200 OK Server: nginx Date: Sat, 10 Nov 2012 20:07:10 GMT Content-Type: text/html Content-Length: 15091 Last-Modified: Wed, 07 Nov 2012 22:33:36 GMT Connection: keep-alive Accept-Ranges: bytes
DNS Record Analysis
There are total 12 records in domain name system (DNS) of 37signals.com, which includes 1 Address(A) record, 5 Mail Exchange(MX) records, 4 Name Server(NS) records, 1 Start of Authority(SOA) record and 1 Text(TXT) record.
Host Name of the node to which this record pertains
Type Type of resource record in symbolic representation.
IP/Target
TTL Count of seconds that the resource record stays valid.
Extra Info Additional resource record-specific data
37signals.com
A Address Record: A 32-bit IPv4 address, most commonly used to map hostnames to an IP address of the host, but also used for DNSBLs, storing subnet masks in RFC 1101.
204.62.114.38
300
37signals.com
MX Mail Exchange Record: Maps a domain name to a list of message transfer agents for that domain.
ASPMX.L.GOOGLE.com
600
pri: 10
37signals.com
MX Mail Exchange Record: Maps a domain name to a list of message transfer agents for that domain.
ALT2.ASPMX.L.GOOGLE.com
600
pri: 30
37signals.com
MX Mail Exchange Record: Maps a domain name to a list of message transfer agents for that domain.
ASPMX2.GOOGLEMAIL.com
600
pri: 40
37signals.com
MX Mail Exchange Record: Maps a domain name to a list of message transfer agents for that domain.
ASPMX3.GOOGLEMAIL.com
600
pri: 40
37signals.com
MX Mail Exchange Record: Maps a domain name to a list of message transfer agents for that domain.
ALT1.ASPMX.L.GOOGLE.com
600
pri: 30
37signals.com
NS Name Server Record: Delegates a DNS zone to use the given authoritative name servers.
ns2.p25.dynect.net
21314
37signals.com
NS Name Server Record: Delegates a DNS zone to use the given authoritative name servers.
ns3.p25.dynect.net
21314
37signals.com
NS Name Server Record: Delegates a DNS zone to use the given authoritative name servers.
ns4.p25.dynect.net
21314
37signals.com
NS Name Server Record: Delegates a DNS zone to use the given authoritative name servers.
ns1.p25.dynect.net
21314
37signals.com
SOA Start of Authority Record: Specifies authoritative information about a DNS zone, including the primary name server, the email of the domain administrator, the domain serial number, and several timers relating to refreshing the zone.
TXT Text Record: Originally for arbitrary human-readable text in a DNS record. Since the early 1990s, however, this record more often carries machine-readable data, such as specified by RFC 1464, opportunistic encryption, Sender Policy Framework, DKIM, DMARC DNS-SD.
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