The ClearCase ALBD (ALBD stands for the Atria Location 
Broker Daemon) Atria was the name of the company that 
originally designed and developed ClearCase) server is a 
broker between ClearCase processes and data. It provides 
other ClearCase processes with the information needed to 
locate and communicate with other ClearCase processes, 
regardless of where in the network the processes exist.

the albd server handles a varienty of tasks.

when a cleint program wants access a service ( avob or view 
serverfor example)on cleracase host,it uses a remote 
procedure call to send a request to the albd server on that 
host. the albd server starts the requested services if it 
is not already started. then isssues a responce telling the 
client the service's port number. thereafetr the client 
communicates directly with the specific service, without 
invoving the albd_server.

responding to requests for registry information on rational 
cleracase registry on server host.

responding to requests for licenses information on a 
rational cleracase license server hpst.

your question is not clear.your are asking albd_server or 
db_server process.But i am explain both process.

albd_server process is very critical service in clearcase 
server and client .
albd_server process responsible:

1.Starting and stopping other Rational ClearCase services 
as needed.
2.Setting up network communications between Rational 
ClearCase clients and servers that time (When a client 
program wants to access a service (a VOB or view server, 
for example) on a Rational ClearCase server host, it uses a 
remote procedure call (RPC) to send a request to the 
albd_server process on that host).
3.Managing execution of tasks run by the Rational ClearCase 
scheduler.
4.Responding to requests for registry information on a 
Rational ClearCase registry server host.
5.Responding to requests for licenses on a Rational 
ClearCase license server host.

albd_server listen RPC port number is port 371.


db_server service is  different for albd_server process .
db_server is dependent process of albd_server process.

Resonsibile for db_server process:

   Client program is not able to access VOB database 
directly. db_server processes manage VOB database 
transactions on that host in response to requests from 
client programs