HP StorageWorks 8/80 HP StorageWorks Fabric OS 6.2 administrator guide (5697-0 - Page 37

IPv6 autoconfiguration IPv6 can assign multiple IP addresses to each network interface. Each interface is configured with a link local address in almost all cases, but this address is accessible only from other hosts on the same network. To provide for wider accessibility, interfaces are typically configured with at least one additional global scope IPv6 address. IPv6 autoconfiguration allows more IPv6 addresses, the number of which is dependent on the number of routers serving the local network and the number of prefixes they advertise. An upgrade from Fabric OS 6.1 or earlier, which does not support IPv6 autoconfiguration, to a platform that does support IPv6 autoconfiguration, such as Fabric OS 6.2 or later, causes IPv6 autoconfiguration to be enabled on the upgraded platform. In upgrades or downgrades between versions of Fabric OS that support autoconfiguration, the enabled state of IPv6 autoconfiguration is not changed. There are two methods of autoconfiguration for IPv6 addresses, stateless and stateful. Stateless allows an IPv6 host to obtain a unique address using the IEEE 802 MAC address; stateful uses a DHCPv6 server which keeps a record of the IP address and other configuration information for the host. Whether a host engages in autoconfiguration and which method it uses is dictated by the routers serving the local network, not by a configuration of the host. There can be multiple routers serving the network, each potentially advertising multiple network prefixes. Thus the host is not in full control of the number of IPv6 addresses that it configures, much less the values of those addresses, and the number and values of addresses can change as routers are added to or removed from the network. When IPv6 autoconfiguration is enabled, the platform engages in stateless IPv6 autoconfiguration. When IPv6 autoconfiguration is disabled, the platform relinquishes usage of any autoconfigured IPv6 addresses that it may have acquired while it was enabled. This same enable and disable state also enables or disables the usage of a link local address for each managed entity, though a link local address continues to be generated for each nonchassis-based platform and for each CP of a chassis-based platform because those link local addresses are required for router discovery. The enabled or disabled state of autoconfiguration is independent of whether any static IPv6 addresses have been configured. Setting IPv6 autoconfiguration 1. Connect to the switch and log in using an account assigned to the admin role. 2. Take the appropriate following action based on whether you want to enable or disable IPv6 autoconfiguration: • Enter the ipAddrSet -ipv6 -auto command to enable IPv6 autoconfiguration for all managed entities on the target platform. • Enter the ipAddrSet -ipv6 -noauto command to disable IPv6 autoconfiguration for all managed entities on the target platform. Date and time settings Switches maintain the current date and time inside a battery-backed real-time clock (RTC) circuit receiving the date and time from the fabric's principal switch. Date and time are used for logging events. Switch operation does not depend on the date and time; a switch with an incorrect date and time value still functions properly. However, because the date and time are used for logging, error detection, and troubleshooting, you should set them correctly. In a Virtual Fabric there can be a maximum of eight Logical Switches per director or enterprise-class platform. Only the default switch in the chassis updates the hardware clock. When the date command is entered from a non-principal pre-Fabric OS 6.2.0 switch, it is dropped by a Fabric OS 6.2.0 switch and the pre-Fabric OS 6.2.0 switch does not receive an error. Authorization access to set or change the date and time for a switch is role-based. For an understanding of role-based access, see "Role-Based Access Control (RBAC)" on page 67. If you are running a Fabric OS version earlier than 6.0.0 and secure mode is not enabled, a change in date or time to one switch is forwarded to the principal switch and distributed to the fabric. If the FCS policy has been set, date or time changes can be made only on the primary FCS switch and distributed to the fabric. Setting the date and time 1. Connect to the switch and log in using an account assigned to the admin role. Fabric OS 6.2 administrator guide 37