>I went back and dug through some of my email, and the issue showed up as >CR 6565042. > >That was fixed in b77 and s10 update 6. > >I looked at this CR, forgive me but I am not a ZFS engineer. Can you explain >in, >simple terms, how ZFS now reacts to this? If it does not panic how does >it insure >data is save?
Found some conflicting information Infodoc: 211349 Solaris[TM] ZFS & Write Failure. "ZFS will handle the drive failures gracefully as part of the BUG 6322646 fix in the case of non-redundant configurations by degrading the pool instead of initiating a system panic with the help of Solaris[TM] FMA framework." >From Richards post above. "NB definitions of the pool states, including "degraded" are in the zpool(1m) man page. -- richard" >From zpool man page located below. http://docs.sun.com/app/docs/doc/819-2240/zpool-1m?l=en&a=view&q=zpool "Device Failure and Recovery ZFS supports a rich set of mechanisms for handling device failure and data corruption. All metadata and data is checksummed, and ZFS automatically repairs bad data from a good copy when corruption is detected. In order to take advantage of these features, a pool must make use of some form of redundancy, using either mirrored or raidz groups. While ZFS supports running in a non-redundant configuration, where each root vdev is simply a disk or file, this is strongly discouraged. A single case of bit corruption can render some or all of your data unavailable. A pool's health status is described by one of three states: online, degraded, or faulted. An online pool has all devices operating normally. A degraded pool is one in which one or more devices have failed, but the data is still available due to a redundant configuration. A faulted pool has corrupted metadata, or one or more faulted devices, and insufficient replicas to continue functioning. The health of the top-level vdev, such as mirror or raidz device, is potentially impacted by the state of its associated vdevs, or component devices. A top-level vdev or component device is in one of the following states:" So from the zpool man page it seems that it is not possible to put a single device zpool in a degraded state. Is this correct or does the fix in Bugs 6565042 and 6322646 change this behavior. > >Also, just want to ensure everyone is on the same page here. There seems to be >>some mixed messages in this thread about how sensitive ZFS is to SAN issues. > >Do we all agree that creating a zpool out of one device in a SAN environment >is >not recommended. One should always constructs a zfs mirror or raidz device >out >of SAN attached devices, as posted in the ZFS FAQ? The zpool man page seem to agree with this. Is this correct? -- This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
