HP StorageWorks 2/16V HP StorageWorks Fabric OS 5.3.x administrator guide (569 - Page 385

Splitting a fabric If the connections between two fabrics are no longer available, the fabric will segment into two separate fabrics. Each new fabric will retain the same zone configuration. If the connections between two fabrics are replaced and no changes have been made to the zone configuration in either of the two fabrics, then the two fabrics will merge back into one single fabric. If any changes that cause a conflict have been made to either zone configuration, then the fabrics might segment. Using Zoning to administer security Zones provide controlled access to fabric segments and establish barriers between operating environments. They isolate systems with different uses, protecting individual systems in a heterogeneous environment; for example, when Zoning is in secure mode, no merge operations occur. Advanced Zoning is configured on the primary Fabric Configuration Server (FCS). The primary FCS switch makes Zoning changes and other security-related changes. The primary FCS switch also distributes Zoning to all other switches in the secure fabric. All existing interfaces can be used to administer Zoning (depending on the policies; refer to the Secure Fabric OS Administrator's Guide for information about security policies). You must perform zone management operations from the primary FCS switch using a zone management interface, such as telnet or Advanced Web Tools. You can alter a Zoning database, provided you are connected to the primary FCS switch. When two secure fabrics join, the traditional Zoning merge does not occur. Instead, a Zoning database is downloaded from the primary FCS switch of the merged secure fabric. When E_Ports are active between two switches, the name of the FCS server and a Zoning policy set version identifier are exchanged between the switches. If the views of the two secure fabrics are the same, the fabric's primary FCS server downloads the Zoning database and security policy sets to each switch in the fabric. If there is a view conflict, the E_Ports are segmented due to incompatible security data. As part of Zoning architecture, you must determine which of the two basic Zoning architectures (hard or soft) works best for your fabric. With time and planning, the basic hard zone configuration works for most sites. If a site has additional security needs, use the additional layer of Secure Fabric OS, apart from the standard Zoning architecture. NOTE: Secure Fabric OS requires the activation of a security license and an Advanced Zoning license. Resolving zone conflicts Zone conflicts can be resolved by saving a configuration file with the configUpload command, examining the Zoning information in the file, and performing a cut and paste operation so that the configuration information matches in the fabrics being merged. After examining the configuration file, you can choose to resolve zone conflicts by using the cfgClear command followed by the cfgDisable command on the incorrectly configured segmented fabric, followed by a portDisable/portEnable command on one of the ISL ports that connects the fabrics. This will cause a merge, making the fabric consistent with the correct configuration. CAUTION: Be careful using the cfgClear command, because it deletes the defined configuration. Table 96 lists considerations for Zoning architecture. Fabric OS 5.3.0 administrator guide 393