Considerations – Upgrade or Create New (VMFS-5)
While a VMFS-3 which is upgraded to VMFS-5 provides you with most of the capabilities as a newly created VMFS-5, there are some differences. Both upgraded and newly created VMFS-5 support single-extent volumes up to 64TB and both support VMDK sizes of ~2TB, no matter what the VMFS file-block size is. However additional differences, although minor, should be considered when making a decision whether to upgrade to VMFS-5 or create new VMFS-5 volumes.
No Uniform Block Size
VMFS-5 upgraded from VMFS-3 continues to use the previous file-block size, which may be larger than the unified 1MB file-block size. This can lead to stranded/unused disk space when there are lots of small files on the datastore.
No New Sub-Block Size
VMFS-5 upgraded from VMFS-3 continues to use 64KB sub-blocks and not the new 8KB sub-blocks. This can also lead to stranded/unused disk space. The upgraded VMFS-5 also continues to use the original number of sub-blocks from the VMFS-3.
No Increase to the Maximum Number of Files per Datastore
VMFS-5 upgraded from VMFS-3 continues to have a file limit of 30,720 rather than new file limit of > 100,000 for newly created VMFS-5. This has an impact on the scalability of the file system.
Uses MBR
VMFS-5 upgraded from VMFS-3 continues to use MBR (Master Boot Record) partition type; when the VMFS-5 volume has grown beyond 2TB, it automatically and seamlessly switches from MBR to GPT (GUID Partition Table) with no impact on the running virtual machines.
Starts on Sector 128
VMFS-5 upgraded from VMFS-3 continues to have its partition starting on sector 128. Newly created VMFS-5 partitions will have their partition starting at sector 2048.
For more details you can see the link below:-
http://www.vmware.com/files/pdf/techpaper/VMFS-5_Upgrade_Considerations.pdf
While a VMFS-3 which is upgraded to VMFS-5 provides you with most of the capabilities as a newly created VMFS-5, there are some differences. Both upgraded and newly created VMFS-5 support single-extent volumes up to 64TB and both support VMDK sizes of ~2TB, no matter what the VMFS file-block size is. However additional differences, although minor, should be considered when making a decision whether to upgrade to VMFS-5 or create new VMFS-5 volumes.
No Uniform Block Size
VMFS-5 upgraded from VMFS-3 continues to use the previous file-block size, which may be larger than the unified 1MB file-block size. This can lead to stranded/unused disk space when there are lots of small files on the datastore.
No New Sub-Block Size
VMFS-5 upgraded from VMFS-3 continues to use 64KB sub-blocks and not the new 8KB sub-blocks. This can also lead to stranded/unused disk space. The upgraded VMFS-5 also continues to use the original number of sub-blocks from the VMFS-3.
No Increase to the Maximum Number of Files per Datastore
VMFS-5 upgraded from VMFS-3 continues to have a file limit of 30,720 rather than new file limit of > 100,000 for newly created VMFS-5. This has an impact on the scalability of the file system.
Uses MBR
VMFS-5 upgraded from VMFS-3 continues to use MBR (Master Boot Record) partition type; when the VMFS-5 volume has grown beyond 2TB, it automatically and seamlessly switches from MBR to GPT (GUID Partition Table) with no impact on the running virtual machines.
Starts on Sector 128
VMFS-5 upgraded from VMFS-3 continues to have its partition starting on sector 128. Newly created VMFS-5 partitions will have their partition starting at sector 2048.
For more details you can see the link below:-
http://www.vmware.com/files/pdf/techpaper/VMFS-5_Upgrade_Considerations.pdf
No comments:
Post a Comment