Directory servers can be protected from directory client access by directory proxy servers. Directory proxy servers hide the implementation details of a directory server deployment from client applications. For details on installing a standalone directory proxy server, see "Installing a Directory Proxy Server".
This chapter covers installation of standalone directory proxy servers. A standalone directory proxy server forwards LDAP requests for user data to remote directory servers. Directory proxy servers make it possible to provide a single point of access to a directory service, and to hide implementation details from client applications.
Unlike standalone directory proxy servers, directory servers store local copies of user data, and can replicate that data with other directory servers. For details on installing a directory server, see "Installing a Directory Server".
This account is used to connect to the remote directory service. The directory proxy server binds with this account, and forwards LDAP requests on behalf of other users. The account must have the same bind DN and bind password on all remote directory servers.
The following example sets up a directory proxy server that discovers remote servers by connecting to a replication server. It forwards all requests to public naming contexts of remote servers. (Generally this means requests targeting user data, as opposed to the proxy's configuration, schema, or monitoring statistics.) It uses the least requests load balancing algorithm:
The following example sets up a directory proxy server that has a static list of remote servers to connect to. It forwards only requests targeting dc=example,dc=com. It uses the default affinity load balancing algorithm:
This mechanism contacts OpenDJ replication servers to discover directory servers to forward LDAP requests to. Each replication server maintains information about the replication topology that allows the proxy server to discover directory server replicas.
In distributed deployments, nearby remote directory servers may be set as primary and others as secondary. The proxy attempts first to forward requests to primary servers. If no primary servers are available, then the proxy forwards requests to secondary servers until the primary servers become available again. This is useful, for example, to prevent a proxy from load balancing some requests over WAN links even though directory servers on the LAN are ready to receive requests. For a replication service discovery mechanism, you identify the primary server group by its replication group ID, as described in "Replication Groups" in the Administration Guide. For a static service discovery mechanism, you enumerate primary and secondary servers.
The connection-level security (SSL, StartTLS) options for the service discover mechanism determine how the proxy secures connections to the remote directory services. Use secure connections in production deployments to avoid sending simple bind (bind DN/password) credentials in cleartext.
A directory proxy server uses a proxy DN and password to connect to remote directory servers, and proxied authorization for forwarded LDAP requests. This proxy account must exist with the same credentials on all remote directory servers, and must be able to use the standard proxied authorization control.
Install an OpenDJ proxy server instance. There are two ways to specify the servers to be contacted by the proxy. They can either be listed exhaustively or retrieved from an existing replication topology. See "setup proxy-server --help" for specific options.
Base DN for user information in the Proxy Server. Multiple base DNs may be provided by using this option multiple times. If no base DNs are defined then the proxy will forward requests to all public naming contexts of the remote servers.
PyPI server isn't responding to your requests. It can happen either because the PyPI server is down or because it has blacklisted your IP address. This happened to me once when I was trying installing packages on a server. This can be fixed by using a proxy with pip. See the solution below.
Methods used by different surveillance systems often vary because of the differing priorities of the agencies collecting the data and because of budget constraints. For example, systems vary in terms of 1) what is measured (e.g., diagnostic criteria for a mental disorder, reports of previously diagnosed conditions, reports of mental health symptoms, or other indicators of mental health problems), 2) sample (e.g., age range, oversampling, and geographical coverage), 3) source of the information (e.g., proxy respondent for the child, self-report by the child, or administrative records), 4) the way the data are collected (e.g., in-person interview, telephone interview, self-administered survey, and administrative records), 5) sample size (precision of estimates), and 6) periodicity of data collection (annual or other). Differences in these surveillance modalities and methods might limit comparisons of estimates between different systems (38). In addition, changes in the characteristics of the same surveillance system over time might limit information about time trends in the prevalence of mental disorders. Information on mental health is collected through independent surveillance systems with varying objectives. 2b1af7f3a8