How DRL's work When the system is rebooted after a 'non-graceful' shutdown, volume manager needs to syncronize the plexes to guarantee that both mirrors are identical. They are not used for on-line reconfigurations operations.Īgain, the DRL is ONLY used if the system crashes and is subsequently rebooted. In the case where a plex is disassociated, this causes the entire plex to go stale, so when you reattach the plex to the mirror, it requires a full resync. This 'feature' or functionality is not part of the design of the Veritas software. In SDS you can do a metaoffline and the SDS DRL keeps track of which regions are changed then when doing a metaonline some time later SDS only resync's the changed regions. In most other scenarios they are not used. The main use for DRLs is in system failure. If one side of a mirror goes down and is marked as bad and needs to be restarted, a full resync will be done and the DRLs have no value. The DRL is not added automatically, because it is an "option" and not always necessary. One mistake people make is assuming that the DRL is the same thing as the log used on a Raid5 volume. How does Dirty Region Logging (DRL) work ?ĭirty Region Logging is a bit map mechanism used to facilitate mirror resynchronisation after a system failure Where DRL's can be usedĪ DRL is ONLY used when a volume has 2 plexes or more (ie, a mirror) and the system panics (or someone yanks out the power cord). This rest of this section is designed to give you an idea of various disk management tips and hints for Volume Manager. Hot-spares only act as replacements for other disk in the same disk group. Volume manger will build a mirror and do a full sync of the original disk to the new disk. usr/sbin/vxassist -g maxsize layout=nologĪn alternative would be to use vxassist. Of course, before moving any relocated subdisks back, ensure the disk that experienced the failure has been fixed.Īn alternative would be to use vxevac. Where disk05 is the 'relocated to' disk and disk02 is the 'relocated from' disk usr/sbin/vxassist -g move !disk05 disk02 Note this is hot sparing and not hot relocation. Where user-name is the user you wish to have mailed. Subject: Attempting VxVM relocation on host xxxĮdit /etc/rc2.d/S95vxvmrecover and enter 'vxsparecheck user-name &' Subject: Volume Manager failures on host xxx How can I set the ownership of a volume ?Ī mail message will have been sent to root (by default) indicating How do I increase the size of a striped mirrored volume ?ħ0. How to import rootdg from another host ?Ħ8. How can I clone a Sparc Storage Array which is under Veritas control ?Ħ7. How does a hotspare know when to kick in ?Ħ6. How do I upgrade to Solaris 2.5 & VM 2.1.1 ?Ħ4. How can I clear subdisks which are in IOFAIL state ?Ħ3. How can I clear the message 'volume ? is locked by another utility' ?Ħ2. What can the vxprivutil command be used for ?Ħ1. Veritas Utilities and Scripts (Unsupported)Ħ0. Official SSA/A5000 Software/Firmware Configuration Matrixĥ7. How can I setup an alternate dump device (rcS.d/S35newdumpdevice) ?ĥ6. How can I add more swap from another disk under Veritas ?ĥ5. How could I backup and restore private regions ?ĥ4. How do I return to underlying devices ?ĥ3. How do I move disks from one disk group to another ?ĥ2. How can I recover a failing disk - FAILING ?ĥ1. What should I consider when configuring swap ?ĥ0. How can I create a small rootdg without encapsulating a disk ?Ĥ8. Where can I get Demo License for VxVM (2.6) ?Ĥ7. Where can I get the latest SSA Matrix - (Patches & Compatibility) ?Ĥ6. How can I grow the private region of a disk group ?Ĥ5. How can I manually failover a diskgroup in an SSA ?Ĥ4. How does Dirty Region Logging (DRL) work ?Ĥ3. Can I use a hot-spare across multiple disk groups ?Ĥ0. Is it safe to use vxevac on a live system ?ģ9. How do I move all the subdisks from one physical disk to another disk ?ģ8. How can I change the name of a VM disk ?ģ7. How can I find out which physical disks are in a disk group ?ģ6. How do I list all the subdisks in my volume ?ģ5. How to determine unused space in a diskgroup config ?ģ4. How do I make Volume Manager see newly added disks ?ģ3. How do I force a disk back into it's original configuration after it has been hot-spared ?ģ2. How do I redirect mail to be sent to another user instead of root in the event of a failure & hot spare replacement ?ģ1. How can I tell if a disk has been hot spared ?ģ0. However, if at all possible, use the GUI.Ģ9. The questions are designed to give you an idea of what goes on in the background. An explanation of why can be seen in Q97. Sun do not normally support this method of bottom up creation of volumes. Note that the first 28 questions have answers related to using the command line.
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |