NSLookup( )
=NsLookup( ) 
How to check, test and evaluate DNS lookup in Microsoft Excel. Supports IPv4 and IPv6 DNS Lookup. Tools for MX record lookup including priorities and ttl
NsLookup( )
additional features now supported in ipte version 3.5
Performs DNS name resolution for the target host or URL/URI. Return results and response time for DNS server performance testing. Local host files are not used. Resolution results are not placed into the system DNS cache. System defined or argument specified name servers are used
>NsLookup Argument RecordType
>NsLookup Argument TimeOut
>NsLookup Argument DNS_Server_IP
>NsLookup Usage Examples
>NsLookup Notes
Arguments
| TargetURL | Required |
May be URL, Host Name or IP Address. Supports IPv6 addresses
| ReturnType | Optional - default is 2 |
0 TrueFalse = TRUE/FALSE
If the TargetURL is resolved then TRUE is returned else the return is FALSE
1 Time = time in milliseconds
Time taken in milliseconds to receive the result from the name server. If the result fails -1 is returned
2 Record = first record, data field
Returns the first record returned by the name server for the requested record type. The data field of the answer is returned. For all 2x return types, if RecordType is omitted then the type A is returned for a host address and the type PTR is returned for an IP address
20 RecordData = first record, data field
Same as 2. Returns the first record returned by the name server for the requested record type. The data field of the answer is returned
21 RecordName = first record, name field
Returns the first record returned by the name server for the requested record type. The name field of the answer is returned
22 RecordTTL = first record, ttl field
Returns the first record returned by the name server for the requested record type. The ttl field of the answer is returned. TTL is time to live. TTL returned value is an integer representing seconds
23 RecordType = first record, type field
Returns the first record returned by the name server for the requested record type. The type field of the answer is returned. Type is an integer and represents a record type defined by various RFCs. Link to Domain Name System Paramaters at IANA: http://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml
24 RecordAllFields = first record, data field<fs>name field<fs>ttl field<fs>type field
Returns the first record returned by the name server for the requested record type. The data, name, ttl and type fields are returned separated by <fs>. Note about <fs> below
25 RecordAllFieldsDescriptions = first record, data field<fs>name field<fs>ttl field<fs>type field
Returns the first record returned by the name server for the requested record type. The data, name, ttl and type fields are returned separated by <fs>. Note about <fs> below. The fields are decorated with descriptions prefixed Data: Name: TTL: Type:
3 AnswerRecords = all records returned, data field, delimited by <fs>
Returns all records returned by the name server for the requested record type. The data field of the answer is returned. For all 3x return types, if RecordType is omitted then the type A is returned for a host address and the type PTR is returned for an IP address
30 AnswerRecordsData = all records returned, data field, delimited by <fs>
Same as 3. Returns all records returned by the name server for the requested record type. The data field of the answer is returned
31 AnswerRecordsName = all records returned, name field, delimited by <fs>
Returns all records returned by the name server for the requested record type. The name field of the answer is returned
32 AnswerRecordsTTL = all records returned, ttl field, delimited by <fs>
Returns all records returned by the name server for the requested record type. The ttl field of the answer is returned. TTL is time to live. TTL returned value is an integer representing seconds
33 AnswerRecordsType = all records returned, type field, delimited by <fs>
Returns all records returned by the name server for the requested record type. The type field of the answer is returned. Type is an integer and represents a record type defined by various RFCs. Link to Domain Name System Paramaters at IANA: http://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml
34 AnswerRecordsAllFields = all records returned, data field<fs>name field<fs>ttl field<fs>type field<fs>
Returns all records returned by the name server for the requested record type. The data, name, ttl and type fields are returned separated by <fs>. Note about <fs> below
35 AnswerRecordsAllFieldsDescriptions = all records returned, data field<fs>name field<fs>ttl field<fs>type field<fs>
Returns all records returned by the name server for the requested record type. The data, name, ttl and type fields are returned separated by <fs>. Note about <fs> below. The fields are decorated with descriptions prefixed Data: Name: TTL: Type:
6 MXRecords = all records returned, hostname, delimited by <fs>
Returns all records returned by the name server for the MX record type. The hostname field of the answer is returned
60 MXRecordsHostName = all records returned, hostname field, delimited by <fs>
Same as 6. Returns all records returned by the name server for the MX record type. The hostname field of the answer is returned
61 MXRecordsIPAddress = all records returned, ipaddress field, delimited by <fs>
Returns all records returned by the name server for the MX record type. The ipaddress field of the answer is returned
62 MXRecordsPreferences = all records returned, preference field, delimited by <fs>
Returns all records returned by the name server for the MX record type. The preference field of the answer is returned
64 MXRecordsAllFields = all records returned, hostname field<fs>ipaddress field<fs>preference field<fs>
Returns all records returned by the name server for the MX record type. The hostname, ipaddress, and preference fields are returned separated by <fs>. Note about <fs> below
65 MXRecordsAllFieldsDescriptions = all records returned, hostname field<fs>ipaddress field<fs>preference field<fs>
Returns all records returned by the name server for the MX record type. The hostname, ipaddress, and preference fields are returned separated by <fs>. Note about <fs> below. The fields are decorated with descriptions prefixed HostName: IPAddress: Preference:
99 FailureReason = error reason
Returns a text string describing the error. If there was no error then the string #ipte_NO-ERROR is returned
| RecordType | Optional – default is PTR if TargetURL is an IPv4 or IPv6 address otherwise A |
1 A = address record
Returns a 32 bit IPv4 address
2 NS = name server
Returns an authoritive name server
5 CNAME = canonical name
Returns a canonical name which is an alias of one name to another
6 SOA = start of authority or authority record
Returns the fields associated with the start of authority record delimited by <fs> The fields are mname, rname, serial, refresh, retry, expire and minimum.
7 MB = mailbox domain name
Returns a mailbox domain name
8 MG = mail group member
Returns a mail group member
9 MR = mail rename domain
Returns mail rename domain
10 NULL = null RR
Returns a null
11 WKS = well known service
Returns a well known service description
12 PTR = pointer record
Returns a pointer to a canonical name or commonly the reverse DNS lookup
13 HINFO = host information
Returns host information
14 MINFO = mailbox or mail list information
Returns mailbox or mail list information
15 MX = mail exchange
Returns a mail exchange record but not the entire record type. Use this type to retrieve the records TTL value. Use the MX return types 6, 60 - 65 for complete MX record lookup information
16 TXT = text strings
Returns text strings
17 RP = resposible person
Returns responsible person
18 AFSDB = afs data base location
Returns afs data base location
19 X25 = x.25 psdn address
Returns x.25 psdn address
20 ISDN = isdn address
Returns isdn address
21 RT = route through
Returns route through
22 NSAP = nsap address
Returns nsap style A record
23 NSAP = nsap pointer
Returns nsap domain name pointer
24 SIG = security signature
Returns security signature
25 KEY = security key
Returns security key
26 PX = x.400 mail mapping
Returns x.400 mail mapping information
27 GPOS = geographical position
Returns geographical position information
28 AAAA = IP6 address
Returns IPv6 addresses. Reference: RFC 3596 http://tools.ietf.org/html/rfc3596
29 LOC = location information
Returns location information
30 NXT = OBSOLETE next domain
Returns next domain information
31 EID = end point identifier
Returns end point identifier information
32 NIMLOC = nimrod locator
Returns nimrod locator information
33 SRV = server selection
Returns server selection information
34 ATMA = atm address
Returns atm address information
35 NAPTR = naming authority pointer
Returns naming authority pointer information
36 KX = key exchanger
Returns key exchanger information
37 CERT = cert
Returns server cert information
39 DNAME = dname selection
Returns dname information
40 SINK = sink information
Returns sink information
41 OPT = opt information
Returns opt information
42 APL = apl information
Returns apl information
43 DS = delegation signer information
Returns delegation signer information
44 SSHFP = ssh key fingerprint
Returns ssh key fingerprint
45 IPSECKEY = ipsec key
Returns ipsec key
46 RRSIG = rrsig
Returns rrsig information
47 NSEC = nsec information
Returns nsec information
48 DNSKEY = dns key information
Returns dns key information
49 DHCID = dhcid information
Returns dhcid information
50 NSEC3 = nsec3 information
Returns nsec3 information
51 NSEC3PARAM = nsec3 param information
Returns nsec3 param information
52 TLSA = tlsa information
Returns tlsa information
55 HIP = host identity protocol information
Returns host identity protocol information
56 NINFO = ninfo information
Returns ninfo information
58 TALINK = trust anchor link information
Returns trust anchor link information
59 CDS = child ds information
Returns child ds information
60 CDNSKEY = dns keys information
Returns dns keys the child wants
61 OPENPGPKEY = open pgp key
Returns open pgp key
99 SPF = sender policy framework
Returns sender policy framework supporting simple email validation information
Reference: RFC 7208 http://tools.ietf.org/html/rfc7208
100 UINFO = uinfo information
Returns uinfo information
101 UID = uid information
Returns uid information
102 GID = gid information
Returns gid information
103 UNSPEC = unspec information
Returns unspec information
104 NID = nid information
Returns nid information
105 L32 = l32 information
Returns l32 information
106 L64 = l64 information
Returns l64 information
107 LP = lp information
Returns lp information
108 EUI48 = eui48 information
Returns eui48 information
109 EUI64 = eui64 information
Returns eui64 information
249 TKEY = transaction key
Returns transaction key
250 TSIG = transaction signature
Returns transaction signature
251 IXFR = incremental transfer
Returns nothing - ipte not implemented
252 AXFR = automatic transfer
Returns nothing - ipte not implemented
253 MAILB = mailbox related information
Returns mailbox related rrs mb mg or mr
254 MAILA = mail agent related information
Returns mail agent information
255 ANY = all records
Returns all records the server or cache has available
255 ALL = all records
Returns all records the server or cache has available
256 URI = uri information
Returns uri information
257 CAA = certificate authority restriction
Returns certificate authority restriction information
32768 TA = dns sec trust authorities
Returns dns sec trust authorities
32769 DLV = dns sec lookaside validation
Returns dns sec lookaside validation
| TimeOut | Optional - default is 1 |
Integer value 1 to 25. Timeout value in seconds. The amount of time to wait for a name server response before returning a timeout error
| DNS_SERVER_IP | Optional – default system defined name servers are used |
IPv4 Address
The specified IP address will be used as the name server to resolve names. If an invalid IPA is specified then the return is #ipte_ARG5-ERROR. The specified name server will be used in this function only. This will be the only name server tried
Usage Examples
=NsLookup(“http://www.cisco.com”)
Performs a lookup on the TargetURL host “www.cisco.com” and returns the first A record returned from the name server
=NsLookup(“184.87.144.170”)
Performs a lookup on the TargetURL host 184.87.144.170 and returns the first PTR record returned because the host is a IPv4 address
=NsLookup("http://att.com","MXRecords")
Performs a lookup on the TargetURL which resolves to “att.com” and returns the host names for the requested type MX records delimited by <fs>. Consider formatting cell as Excel Wrap Text
=NsLookup("http://att.com","AnswerRecordsTTL" ,"MX")
Performs a lookup on the TargetURL which resolves to “att.com” and returns the TTL field for the requested type MX delimited by <fs>. Consider formatting cell as Excel Wrap Text
=NsLookup("www.cisco.com",0)
Performs a lookup on the TargetURL host “www.cisco.com” and returns TRUE if the lookup was successful
=NsLookup("www.juniper.net",1)
Performs a lookup on the TargetURL host “www.juniper.net” and returns the time taken in milliseconds to receive the results from the name server
=NsLookup("CheckTheNetwork.com",,,2,”66.80.130.23”)
Performs a lookup on the TargetURL host “CheckTheNetwork.com” The name server at IP address 66.80.130.23 is used to resolve the request. TimeOut is 2 seconds
=NsLookup("https://YouTube.com","AnswerRecordsData" "AAAA")
Performs a lookup on the TargetURL host “YouTube.com” . Requested return type is all answer records data field for record type AAAA. This will display IPv6 name service information, the IPv6 address(es)
Notes
Any argument can be a cell reference like A7 or $D$3
Arguments can be entered as “string” or number value
Default timeout value for DNS resolution is 1 second. The request is tried 1 time
If your request is for a RecordType that is invalid for the TargetURL then an empty string is returned
Return types in the 3x range and other types that contain <fs> display better when the Excel column is formatted with Wrap Text. Home > Alignment > Wrap Text
<fs> Field Separator presently equivalent to chr(10), which is also LF, which is also line feed. In an Excel Cell with text formatted as Wrap Text this is equivalent to <altl><enter> which forces the text onto the next line
<fs> Wrap Text formatted cells can also display better with a fixed width font sucha as Lucida Console