Modifying Host Cell Name Information
Using the hostdata object, you can add, change, and remove data items on DCE hosts. While administrators will find this useful for modifying a host's cell name or cell alias information, they can also operate on other data that is accessible on a host.
Each DCE host maintains a protected local copy of the cell name and cell aliases of the cell in which the host is registered. Hosts keep this information in a local file called dcelocal/dce_cf.db which is owned by root. Hosts use this information for authentication purposes - as part of its host identity information.
Although host cell name information tends to be fairly stable, there are circumstances where it is necessary to change this information:
· When a host moves to a different cell.
· When a host's cell name changes or the cell name acquires an alias.
When either of these situations occurs however, it's usually not enough to just update the cell name information on the host. Cell name information must also be updated in CDS and in the DCE security service registry as well. For these purposes, the DCE control program provides the host and cellalias task objects which update cell name information wherever it needs to be changed.
When a host moves to a different cell you should usually perform a host unconfigure operation to remove the host from one cell. Then run a host configure operation to establish the host in the new cell. For details on using the host task object, refer to the topic titled Managing DCE Hosts.
When a host's cell name changes or the cell name acquires an alias, you should perform a cellalias operation which updates cell information in CDS, in the DCE Security Service registry, and in the dce_cf.db file of every affected host in the cell. For details on using the cellalias task object, refer to the topic titled Managing Your Cell Name.
Sometimes however, the higher-level dcecp task objects do not offer enough control such as you might need when fixing a corrupted file somewhere or when configuring a host by hand for some reason. In these cases, you can use the hostdata object to change cellname information on individual hosts.
Note though, that this use of the hostdata object is intended mostly to be a troubleshooting operation to be relied on when a host's cell information is out of synchronization with other cell information stored in the DCE registry or stored in CDS. This situation might be a common occurrence in cells with many hosts.
To update the cellname or cell alias name information on a host, use the hostdata object. The following example catalogs the hostdata objects in the cell named /.../my_cell.goodco.com. Then it shows the contents of the cell_name object on host silver. Finally it modifies the cellname to be /.../my_cell.goodco.com on host silver.
dcecp> hostdata cat
/.../my_cell.goodco.com/bronze/config/hostdata/dce_cf.db
/.../my_cell.goodco.com/bronze/config/hostdata/cell_name
/.../my_cell.goodco.com/bronze/config/hostdata/host_name
/.../my_cell.goodco.com/bronze/config/hostdata/cell_aliases
/.../my_cell.goodco.com/bronze/config/hostdata/post_processors
dcecp> hostdata show cell_name
{uuid 00174f6c-6eca-1d6a-bf90-0000c09ce054}
{annotation {Name of cell}}
{storage cell_name}
{data {/.../old_cell.goodco.com}}
dcecp> hostdata modify \
> /.../my_cell.goodco.com/hosts/bronze/config/hostdata/cell_name \
> -data {/.../my_cell.goodco.com}}
dcecp>