Explanation
This message is the first in a group of messages
displayed when resolution of a host name owned by a remote node into
an IP address is attempted but was unsuccessful. Name-to-address
resolution is attempted as part of the following:
- LU-LU session activation when the session route traverses an Enterprise
Extender connection network and the remote endpoint provides a host
name, either instead of or in addition to an IP address, in the APPN
Route Selection Control Vector (RSCV) representing the session route.
- VARY ACT command processing for a switched major node when the
HOSTNAME operand was coded on the PATH statement.
- DISPLAY EE or DISPLAY EEDIAG command was issued which specified
a remote HOSTNAME filter.
The complete message group in these situations is:
IST1893I NAME-TO-ADDRESS RESOLUTION FAILED
IST1909I REMOTE HOSTNAME value
[IST1911I value]
IST314I END
This message is also the first message
in a group of messages displayed when resolution of a locally owned
host name into an IP address was unsuccessfully attempted. This type
of name-to-address resolution is attempted as part of the following:
- VARY ACT command processing for a line defined under a GROUP in
an XCA major node when HOSTNAME was coded on the GROUP statement or
was inherited from the HOSTNAME start option.
- DISPLAY EE or DISPLAY EEDIAG command was issued which specified
a local HOSTNAME filter.
The complete message group in these situations is:
IST1893I NAME-TO-ADDRESS RESOLUTION FAILED
IST1910I LOCAL HOSTNAME value
[IST1911I value]
IST314I END
IST1909I - value is the host name owned by a remote node
for which name-to-address resolution was attempted. If the host name
is longer than 44 characters, then the first 44 characters are displayed
as value and the remaining characters are displayed
in one or more IST1911I messages.
IST1910I - value is the locally owned host name for which
name-to-address resolution was attempted. If the host name is longer
than 45 characters, then the first 45 characters are displayed as value and
the remaining characters are displayed in one or more IST1911I messages.
IST1911I - value is the continuation of value on IST1909I
or IST1910I. IST1911I is repeated as often as necessary to display
the entire character string.
System action
- For LU-LU session processing:
- In addition to its host name, if the target endpoint did not
supply an IP address in the APPN RSCV, then session activation fails.
If an IP address was supplied in addition to the host name, then
processing continues with an attempt to use the supplied IP address
to establish an IP connection.
- For VARY ACT processing:
- The resource activation fails.
- For DISPLAY EE or DISPLAY EEDIAG processing:
- The display command is not performed.
Operator response
Save the system log for problem determination.
For DISPLAY EE or DISPLAY EEDIAG processing, determine whether the
correct host name value is being resolved. If you specified an incorrect
host name, issue the display command again specifying the correct
host names.
System programmer response
- For LU-LU session processing:
- Determine if the correct host name value is being supplied by
the remote node on the APPN RSCV, and if not, update the appropriate
start option or XCA major node definition with the correct HOSTNAME.
- If the correct host name is being supplied, verify that the name-to-address
resolution mapping for the host name yields the desired static VIPA
address (if on a z/OS® host)
of the node that owns the host name, or that it yields the correct
network address translation (NAT) address to ultimately reach the
target static VIPA address of the node that owns the host name. If
the resolution is not correct, update the DNS zone files or local
host files with the corrected name-to-address resolution. If the
resolution is intended to yield an IPv6 address, ensure that the
TCP/IP stack is enabled for IPv6 processing so that the resolver will
search for IPv6 addresses.
- For VARY ACT command processing when activating an XCA major node:
- Determine if the correct host name value is being resolved. If
the activation is using an incorrect host name, do one of the following:
- If the failing host name is a local host name acquired from the
start option, use MODIFY VTAMOPTS to correct the HOSTNAME start option.
- If the failing host name is a local host name defined on the
GROUP definition statement, deactivate the XCA major node, define
the correct HOSTNAME on the appropriate GROUP definition statement,
and reactivate the XCA major node.
- If the correct host name is being supplied, verify that the name-to-address
resolution mapping for the host name yields the desired static VIPA
address on this node. If the resolution is not correct, update the
DNS zone files or the appropriate local hosts files with the corrected
name-to-address resolution. If the resolution is intended to yield
an IPv6 address, ensure that the TCP/IP stack is enabled for IPv6
processing and that at least one TCP/IP IPv6 interface is active,
so that the resolver will search for IPv6 addresses.
- If name-to-address resolution processing is taking a long time,
(for example, because the SEARCH directive in the TCP/IP Resolver
Configuration file specifies a large number of domain names) the
resolution attempt might be abandoned by VTAM® before it can successfully complete due
to the setting of the IPRESOLV operand on the PORT definition statement
associated with the XCA major node. If that is the case, increase
the value of the IPRESOLV operand on the PORT definition statement.
- For VARY ACT command processing when activating a switched major
node:
- Determine if the correct host name value is being resolved. If
the activation is using the incorrect host name, deactivate the switched
major node, define the correct HOSTNAME on the appropriate PATH definition
statement, and reactivate the switched major node.
- If the correct host name is being supplied, verify that the name-to-address
resolution mapping for the host name yields the desired static VIPA
address (if on a z/OS host)
of the node that owns the host name, or that it yields the correct
network address translation (NAT) address to ultimately reach the
target static VIPA address of the node that owns the host name. If
the resolution is not correct, update the DNS zone files or the appropriate
local hosts files with the corrected name-to-address resolution.
If the resolution is intended to yield an IPv6 address, ensure that
the TCP/IP stack is enabled for IPv6 processing so that the resolver
will search for IPv6 addresses.
- If name-to-address resolution processing is taking a long time,
(for example, because the SEARCH directive in the TCP/IP Resolver
Configuration file specifies a large number of domain names) the
resolution attempt might be abandoned by VTAM before it can successfully complete due
to the setting of the IPRESOLV operand on the PATH definition statement.
If that is the case, increase the value of the IPRESOLV operand on
the PATH definition statement.
- For DISPLAY EE or DISPLAY EEDIAG command processing:
- If the correct host name is being supplied on the display command,
verify the following:
- The name-to-address resolution mapping for the host name yields
the correct static VIPA address (if on a z/OS or OS/390® host)
of the node that owns the host name.
- If network address translation (NAT) is in use, the name-to-adress
resolution mapping for the host name yields the correct NAT address
to ultimately reach the target static VIPA address of the node that
owns the host name.
- If the resolution is not correct, update the DNS zone files or
the appropriate local hosts files with the corrected name-to-address
resolution. If the resolution is intended to yield an IPv6 address,
ensure that the TCP/IP stack is enabled for IPv6 processing so that
the resolver searches for IPv6 addresses.
Routing code
Descriptor code