| Where allowed to run: All environments (*ALL) Threadsafe: No |
Parameters Examples Error messages |
The Change TCP/IP Domain (CHGTCPDMN) command is used to specify this system's TCP/IP host and domain name and to configure the Domain Name Server (DNS) information for this system.
Restrictions:
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| Keyword | Description | Choices | Notes |
|---|---|---|---|
| HOSTNAME | Host name | Character value, *SAME, *NONE | Optional |
| DMNNAME | Domain name | Character value, *SAME, *NONE | Optional |
| DMNSCHLIST | Domain search list | Character value, *SAME, *DFT | Optional |
| HOSTSCHPTY | Host name search priority | *REMOTE, *LOCAL, *SAME | Optional |
| INTNETADR | Domain name server | Element list | Optional |
| Element 1: Internet address | Character value, *SAME, *NONE | ||
| Element 2: Internet address | Character value, *SAME, *NONE | ||
| Element 3: Internet address | Character value, *SAME, *NONE | ||
| PORT | Port | 1-65535, *SAME | Optional |
| PROTOCOL | Protocol | *UDP, *TCP, *SAME | Optional |
| INLDMNSVR | Initial domain name server | *FIRST, *ROTATE, *SAME | Optional |
| DMNSVRRTY | Domain name server retry | Element list | Optional |
| Element 1: Number of retries | 1-99, *SAME | ||
| Element 2: Initial time interval | 1-99, *SAME |
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Specify the TCP/IP host name of this system.
Note: This system's TCP/IP host name must also be defined in the local host table or the Domain Name Server (DNS) specified in the INTNETADR parameter. If no DNS is specified, the local TCP/IP host table is used.
The first and last characters of the host name must be an alphabetical character or a digit.
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Specify the name of the TCP/IP domain this host is a member of.
The DMNNAME parameter combined with the HOSTNAME parameter must be less than 255 characters in length.
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Specify the TCP/IP domains to search when fully-qualified domain names (FQDN) are not given. The first name in the search list is the default domain name on all searches.
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Specifies whether to search a Domain Name Server (DNS) first to resolve a TCP/IP host name conflict, or to search the local TCP/IP host table first.
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Specifies up to three Domain Name Servers (DNS) to be used by this system. Specify a DNS by entering its internet address. You may add none, one, two, or three DNS internet addresses.
If the first DNS in the list does not respond, the second DNS server in the list will be contacted. If the second DNS server does not respond, the third DNS server will contacted.
A DNS IPv4 internet address is specified in the form nnn.nnn.nnn.nnn, where nnn is a decimal number ranging from 0 through 255.
An IPv6 internet address is specified in the form x:x:x:x:x:x:x:x, where x is a hexadecimal number ranging from 0 through X'FFFF'. "::" may be used once in the IPv6 address to indicate one or more groups of 16 bits of zeros. The "::" may be used to compress leading, imbedded, or trailing zeros in the address.
An IPv4-mapped IPv6 address may be specified. An IPv4-mapped IPv6 address is specified in the form ::FFFF:nnn.nnn.nnn.nnn, where nnn is a decimal number ranging from 0 through 255.
Element 1: Internet address
Element 2: Internet address
Element 3: Internet address
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Use this parameter to specify the remote TCP/IP port number used to contact the Domain Name Server (DNS) or Servers listed in the INTNETADR parameter. 53 is the well-known port used for this purpose.
Note: Use of a TCP/IP port number other than the well-known port 53 for use by the Domain Name Server (DNS) can result in TCP/IP communication problems. You may inadvertently use a port number which is reserved for use by another TCP/IP application.
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Specify the TCP/IP protocol used to communicate with the Domain Name Server (DNS) specified in the INTNETADR parameter. User Datagram Protocol (UDP) is typically used for this purpose. Use *TCP only if your Domain Name Server (DNS) is specifically configured to use the Transmission Control Protocol (TCP).
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Specify the initial domain name server selection method. This option determines whether the first configured Domain Name Server (DNS) should always be queried first, or if the first name server to be queried should be rotated in a round robin fashion if more than one is configured. This rotation provides a simple form of load balancing on the configured name servers.
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The Domain Name Server Retry (DMNSVRRTY) parameter consists of two elements: number of retries and initial time interval.
Number of retries specifies the number of additional attempts made to establish communication with each Domain Name Server (DNS) specified in the INTNETADR parameter in the event that the first attempt fails.
Initial time interval specifies the initial interval in seconds between retries. For each subsequent retry attempt, the time interval is doubled to a maximum of 120 seconds. For example, if number of retries is 4 and initial time interval is 2, the first retry would occur 2 seconds after the initial attempt to contact the DNS. The second retry would occur 4 seconds after the first retry, the third retry occurs 8 seconds after the second retry, and the fourth retry occurs 16 seconds after the third retry.
Element 1: Number of retries
Element 2: Initial time interval
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Example 1: Change Host and Domain Names
CHGTCPDMN HOSTNAME(rs021) DMNNAME(endicott.ibm.com)
This command changes the host name and domain name.
Example 2: Change Domain Search List
CHGTCPDMN DMNSCHLIST('endicott.ibm.com
rochester.ibm.com
ibm.com')
This command changes the domain search list to be three domain names: endicott.ibm.com, rochester.ibm.com, and ibm.com.
Example 3: Change Domain Name Servers
CHGTCPDMN INTNETADR('9.131.42.251' '5678::1234' *NONE)
This command specifies two domain name server addresses: 9.131.42.251 and 5678::1234.
Example 4: Change Domain Name Server Rotation
CHGTCPDMN INLDMNSVR(*ROTATE)
This command changes the initial domain name server selection so it rotates between the configured name servers in a round robin fashion.
Example 5: Change Domain Name Server Retry
CHGTCPDMN DMNSVRRTY(3 10)
This command changes the domain name server retry values. It sets the number of retries to three and the interval between each retry to ten seconds.
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*ESCAPE Messages
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