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#ident "%Z%%M% %I% %E% SMI"

NIS+ public module

==================

This public module is intended as a replacement for the NIS+

functionality contained in the previous version of the DHCP service

(Solaris 2.6-8).

Differences

===========

This NIS+ module functionality differs from the previous version in a

number of ways:

1) Container names contain container format version:

Container PreEnterprise Form Enterprise Form

========= ================== ===============

dhcptab dhcptab SUNWnisplus1_dhcptab

dhcp network 129_148_174_0 SUNWnisplus1_129_148_174_000

2) Table types are different:

Container PreEnterprise Type Enterprise Type

========= ================== ===============

dhcptab dhcp_tbl SUNW_dhcpsvc_tab

dhcp network dhcp_ip_tbl SUNW_dhcpsvc_net

3) The container (table) format for dhcp network tables is different.

What was the 'flags' field is now broken up into individual searchable

fields for each flag value, with a setting of '1' for TRUE and '0' for

FALSE. This change permits efficient queries by flag value.

4) Blocking/Nonblocking semantics. NIS+ containers now are by default

opened in blocking mode, which means lookups/lists are done using

HARD_LOOKUP, and updates that would have failed in the past with

TRYAGAIN now pause and retry the operation until successful. Opening a

container in nonblocking mode means that DSVC_BUSY is handed to the

caller if the master for the directory is currently busy (operation

failed).

5) It's faster than the previous version.

6) Permits atomic update of records where the unique combination of key

fields is changed.

Notes

=====

One of the planned features for this module was the detection of the

master server needing its transaction log rolled. Unfortunately, I

couldn't do this since the statistics currently generated and made

available to callers through the interface do not include:

a) Size of the transaction log

b) Whether a checkpoint has already been scheduled.

Since rolling the transaction log is uniquely a NIS+ issue with nothing

to do with DHCP, the correct way to solve this problem would be to

modify the rpc.nisd daemon and allow the specification of a transaction

log size threshold, which when reached would cause the daemon to perform

the checkpoint automatically. The RFE is 4354503.

Conversion of old format NIS+ tables

====================================

A nisplus0 public module which provides readonly access to the legacy

tables is available, which enables the user to use the dhcpmgr data

store conversion feature to convert their legacy tables to the new

format.