Siemens V4.0 manual Constraints on high availability

Tools for special tasks OBSERVE support

7.5.1 Constraints on high availability

The following conditions must be fulfilled in order to ensure the concept outlined here of high availability for systems:

–Both servers must be operated in one domain.

–If a system fails, a “reconnect” is necessary for the PCs connected (and possibly also a restart).

–The additional network interface available in each system does not supply data from the network under normal operating conditions.

–The switching of disk areas and the uniqueness of resource names is guaranteed.

–The administrator must be able to export all access permissions.

–In order to switch disk areas to the system that is now operational again, the alternative PCs must log off and then connect again after a successful switchover.

–Resources cannot be set up for a system while it is down.

–If the Primary Domain Controller (PDC) in a domain has failed, it will not be possible to modify users and groups for the duration of the down time.

–Access permissions for the failed system can only be updated to the status of the last “ACL backup”.

–Only one of the servers is to provide “Print” shares.

–Configuration changes (e.g. additional shares) in emergency mode no longer exist once normal operation is resumed.

–If the WINS service is configured on one of the systems, it is not possible for the remaining system to take over the WINS service in the case of a failure.

However, you can provide high avaliability of the WINS service - independently of OBSERVE - by configuring both systems as WINS servers and let these replicate with each other.

Product Manual U7613-J-Z815-6-76