SMTP RESOLVER trace

The RESOLVER trace shows requests and responses sent to and received from name servers. It also shows if local hosts tables are used for name resolution. This trace helps you diagnose problems with host name resolution.

RESOLVER trace output from SMTP is included in the job log output from the started SMTP procedure.

Figure 1 shows an example of RESOLVER trace output. Short descriptions of the numbered items in the trace follow the figure.

Figure 1. Example of RESOLVER trace output

    Userid of Caller:         ARMSTRNG
    TCP Host Name:            RALVMFE1
    Domain Origin:            RALEIGH.IBM.COM
    Jobname of TCP/IP:        TCPCS
    Communicate Via:          UDP
    OpenTimeOut:              30
    MaxRetrys:                1
    NSPort:                   53
    NameServer Userid:        NAMESRV
 1  NSInternetAddress(.1.) := 9.67.1.5
    NSInternetAddress(.2.) := 9.67.5.44
    Data set prefix used:     TCPCS.BTA1
 
    Resolving Name:           RICKA
    Result from InitResolver: OK
    Building Name Server Query:
    * * * * * Beginning of Message * * * * *
 2  Query Id:                 1
 3  Flags:                    0000 0001 0000 0000
    Number of Question RRs:   1
 4  Question   1: RICKA.RALEIGH.IBM.COM A IN
    Number of Answer RRs:     0
    Number of Authority RRs:  0
    Number of Additional RRs: 0
    * * * * * End of Message * * * * *
 5  Sending Query to Name Server at 9.67.1.5 Result: OK
 6  Notification Arrived: UDP data delivered RC = OK
 7  UDP Data Length: 55
    Return from WaitForAnswer: OK
    * * * * * Beginning of Message * * * * *
    Query Id:                 1
    Flags:                    1000 0101 1000 0000
    Number of Question RRs:   1
    Question   1: RICKA.RALEIGH.IBM.COM A IN
    Number of Answer RRs:     1
 8  Answer     1: RICKA.RALEIGH.IBM.COM 86400 A IN 9.67.97.3
    Number of Authority RRs:  0
    Number of Additional RRs: 0
    * * * * * End of Message * * * * *
    HostNumber (1) is: 9.67.97.3

Following are short descriptions of the numbered items in the trace.

1

Address of the name server being used for name resolution. The address is pulled from the TCPIP.DATA data set.

2

Identification number of the query. This is also returned in the response and should be used to match queries to responses.

3

Bits set to determine the type of query and response. (See RFC 1035.) There are 16 bits (0–15) set in the parameter field of DNS message.

Bit

Meaning

0

Operation: 0=query, 1=response

1–4

Query type: 0=standard, 1=inverse

5

Set if the answer is authoritative

6

Set if the message is truncated

7

Set if recursion is wanted

8

Set if recursion is available

9–11

Reserved

12–15

Response type

Value: Meaning
0: No error
1: Format error in query
2: Server failure
3: Name does not exist

4

Actual question sent to the name server

5

IP address of the name server being queried

6

The response has arrived (UDP in this case)

7

Length of the record

8

Answer to the question