Configuration Parameters

This section describes the information you supply to the hadsconfig(1M) command to create configuration files Sun Cluster HA for DNS. The hadsconfig(1M) command uses templates to create these configuration files. The templates contain some default, some hardcoded, and some unspecified parameters. Accept the default values where possible. You must provide values for all parameters that are unspecified.

The fault probe parameters, in particular, can affect the performance of Sun Cluster HA for DNS. Tuning the probe interval value too low (increasing the frequency of fault probes) might encumber system performance, and also might result in false takeovers or attempted restarts when the system is simply slow.

The Sun Cluster HA for DNS data service requires you to set the takeover flag. This flag specifies how Sun Cluster will handle partial failover. There are two options:

• y (yes) - Sun Cluster will attempt to switch over the logical host to another master, but if the attempt fails the logical host will remain on the original master.

• n (no) - Sun Cluster will not move the logical host to another master, even if it detects problems with the data server, nor will it take any action against the sick data server or database on the logical host.

---

Note -

The behavior of DNS changes between Solaris 2.6 and Solaris 8. This is because the default bind version differs between these operating environments. This change requires an update to some DNS configuration files. See your DNS documentation for details and instructions.

---

Configure the Sun Cluster HA for DNS parameters listed in the hadsconfig(1M) input form by supplying options described in Table 12-1.

Table 12-1 Configuration Parameters for Sun Cluster HA for DNS

Parameter	Description
Name of the instance	Nametag used as an identifier for the instance. The log messages generated by Sun Cluster refer to this nametag. The hadsconfig(1M) command prefixes the package name to the value you supply here. For example, if you specify "nsdns_119," hadsconfig(1M) produces "SUNWscdns_nsdns_119."
Logical host	Name of logical host that provides Sun Cluster HA for DNS service.
Configuration directory	Rooted path name specifying the directory of DNS configuration files and database on multihost disk.
Takeover flag	Specifies whether a failure of this instance will cause a takeover or failover of the logical host associated with the data service instance. Possible values are y (yes) and n (no).
Time between probes	The interval, in seconds, of the fault probing cycle. Accept the default value of 60 seconds.
Probe timeout	The time, in seconds, after which a fault probe will time out. The default timeout value is 60 seconds.