[gpfsug-discuss] GPFS magic options for Samba

[Jonathan Buzzard]

Jonathan Buzzard wrote:
> 
> Not documented, but I believe there are four ;-)
> 
>    allowSambaCaseInsensitiveLookup
>    syncSambaMetadataOps
>    cifsBypassShareLocksOnRename
>    cifsBypassTraversalChecking
> 

Just add to this I believe there are some more, mostly because they are 
between the first two and last two in mmchconfig Korn shell file

They are

      allowSynchronousFcntlRetries
      allowWriteWithDeleteChild

Not sure what the first one does, but the second one I am guessing 
allows you to write to a folder if you can delete child folders and 
would make GPFS/Samba follow Windows schematics closer. Over the coming 
days I hope to play around with some of these options and see what they do.

Also there is an undocumented option for ACL's on mmchfs (I am working 
on 3.4.0-13 here so it's not even 3.5) so that you can do

      mmchfs test -k samba

and then

[root at krebs1 bin]# mmlsfs test
flag                value                    description
------------------- ------------------------ 
-----------------------------------
  -f                 32768                    Minimum fragment size in bytes
  -i                 512                      Inode size in bytes
  -I                 32768                    Indirect block size in bytes
  -m                 1                        Default number of metadata 
replicas
  -M                 2                        Maximum number of metadata 
replicas
  -r                 1                        Default number of data 
replicas
  -R                 2                        Maximum number of data 
replicas
  -j                 cluster                  Block allocation type
  -D                 nfs4                     File locking semantics in 
effect
  -k                 samba                    ACL semantics in effect
  -n                 32                       Estimated number of nodes 
that will mount file system
  -B                 1048576                  Block size
  -Q                 user;group;fileset       Quotas enforced
                     none                     Default quotas enabled
  --filesetdf        no                       Fileset df enabled?
  -V                 12.07 (3.4.0.4)          Current file system version
                     11.05 (3.3.0.2)          Original file system version
  --create-time      Fri Dec  4 09:37:28 2009 File system creation time
  -u                 yes                      Support for large LUNs?
  -z                 yes                      Is DMAPI enabled?
  -L                 4194304                  Logfile size
  -E                 no                       Exact mtime mount option
  -S                 no                       Suppress atime mount option
  -K                 always                   Strict replica allocation 
option
  --fastea           yes                      Fast external attributes 
enabled?
  --inode-limit      1427760                  Maximum number of inodes
  -P                 system;nearline          Disk storage pools in file 
system
  -d 
gpfs19nsd;gpfs20nsd;gpfs21nsd;gpfs22nsd;gpfs23nsd;gpfs24nsd  Disks in 
file system
  -A                 yes                      Automatic mount option
  -o                 none                     Additional mount options
  -T                 /test                    Default mount point
  --mount-priority   0                        Mount priority


Not entirely sure what samba ACL's are mind you. Does it modify NFSv4 
ACL's so they follow NTFS schematics more closely?


JAB.

-- 
Jonathan A. Buzzard                      Tel: +441382-386998
Storage Administrator, College of Life Sciences
University of Dundee, DD1 5EH