[NTLUG:Discuss] Re: Creating a shared folder -- disk label recommendations ...

[Bryan J. Smith]

On Mon, 2004-09-27 at 01:01, Bryan J. Smith wrote:
> ... but given that you didn't lay out any special filesystems in the
> first place, it will do.
> P.S.  Typically you should _avoid_ creating new TLDs (top level
> directories).  They are wholly unnecessary under UNIX/Linux, and go
> against the Linux Filesystem Hierarchy Standard (FHS).

SYSTEM Slices (Partitions):  Absolutely Required
- /
- swap
- /var (and symlink /tmp -> /var/tmp)

SYSTEM Slices:  Additional Recommendations
- /tmp (no symlink from /tmp -> /var/tmp)
- /usr
- /home (if not NFS mounted)

WORKSTATION Slices:  Additional Recommendations
- /usr/local (and symlink /opt -> /usr/local)
- /home/(systemname)

SERVER Slices:  Additional Recommendations
- /srv
- /var/spool
- consider additional "service-specific" directories
  E.g., /srv/www, /var/lib/pgsql, /var/spool/squid, etc...

GENERAL GUIDELINES:  

1.  Try to make sets of slices (partitions) of the same size
  A.  This will make it easier to move things around if necessary
  B.  Use same size for all SYSTEM, WORKSTATION and/or SERVER

2.  SYSTEM Slice Recommendations
  A.  4GB "minimum" size for today's 8GB+ disks
  B.  Reserve 1-2 "primary" slices (if using DOS disk label)

3.  WORKSTATION/SERVER Slice Recommendations
  A.  8-64GB+ "typical" size for most additional types
  B.  Reserve at least 1 slice of same size

4.  Disk label format/layout considerations
  A.  Linux-only:  DOS disk label ("Basic Disk")
    (3) 4GB "primary" (83h) + (1) LVM (8Eh)
  B.  Legacy Dual-boot:  DOS disk label ("Basic Disk")
    (1) FAT32 (0Ch) + (2) 4GB "primary" (83h) + (1) LVM (8Eh)
  C.  NT5+ Dual-boot:  LDM disk label ("Dynamic Disk")
    (1) LDM (42h), or
    (2) 4GB "primary" (83h) + (1) LDM (42h) + (1) LVM (8Eh)

5.  Disk array considerations
  A.  Non-data (SYSTEM) should be on RAID-1 or 0+1
  B.  Data can be on SYSTEM, or own (DATA) RAID-0+1, 4 or 5

EXAMPLE DISK LABEL CONFIGURATIONS:  

- Linux Server
  Pri  4GB "spare" (93h)
  Pri  4GB "spare" (93h)
  Pri  4GB / (83h)
  Pri xxGB LVM (8Eh)
           Vol00  4GB swap
           Vol01  4GB /tmp
           Vol02  4GB /var
           Vol03 16GB /usr
           Vol04 16GB /srv
           Vol05 16GB /var/spool
  (NOTE: following could be on different disks, arrays, servers)
           Volxx xxGB (application-specific)
           Volxx xxGB /home/static (read-only files)
           Volxx xxGB /home/(server name or dept)

- Linux-only Workstation
  Pri  4GB "spare" (93h)
  Pri  4GB "spare" (93h)
  Pri  4GB / (83h)
  Pri xxGB LVM (8Eh)
           Vol00  4GB swap
           Vol01  4GB /tmp
           Vol02  4GB /var
           Vol03 16GB /usr
           Vol04 16GB /usr/local
  (NOTE: following could be on different disks, arrays, servers)
           Vol05 xxGB /home/(workstation name)

- Legacy DOS-NT/Linux Dual-boot
  NOTE:  Requires post-1997 (non-buggy) BIOS and sub-137GB (128GiB) disk
  Pri xxGB FAT32 (0Ch)
  Pri  4GB "spare" (93h)
  Pri  4GB / (83h)
  Pri xxGB LVM (8Eh)
           (as Linux-only Workstation above)

- NT5+/Linux Workstation Option 1:  _True_ "Dynamic Disk"
  Create with NT5+ _first_, let it set geometry
  NOTE:  Requires _manual_ disk labeling/tools and LILO as boot loader
  Pri xxGB LDM (42h)
           Vol00 xxGB NTFS
           Vol01  4GB /
           Vol02  4GB /tmp
           Vol03  4GB /var
           Vol04 16GB /usr
           Vol05 16GB /usr/local
           Vol06 16GB /home/(workstation name)
     
- NT5+/Linux Workstation Option 2:  _Partial_ "Dynamic Disk"
  Create with Linux _first_, always _force_ 255/63 heads/sectors geom
  NOTE:  May get "screwed up" by NT5+ tools
  Pri  4GB "spare" (93h)
  Pri  4GB / (83h)
  Pri xxGB LDM (42h)
           Vol00 xxGB NTFS
  Pri xxGB LVM (8Eh)
           (as Linux-only Workstation above)

FINAL NOTES/RECOMMENDATIONS

6.  Common ATA disks rated for only ~15,000 hours (14x5 @ 1 year)
  A.  Consider RAID-1 as a standard option for workstations too
  B.  Do _not_ use "cheap" FRAID, use either software or _real_ hardware
  C.  $125 3Ware Escalade has GPL driver, removes chipset issues, etc...

7.  Avoid dual-booting NT5+ with any other version of NT, or Linux
  A.  Using LDM disk label ("dynamic disks") solves issue for NT5+
  B.  Linux kernel reads LDM, but no GRUB/good user-space support yet
  C.  Use "Option 2" for now, but avoid using NT5+ tools


-- 
Bryan J. Smith                                  b.j.smith at ieee.org 
------------------------------------------------------------------ 
"Communities don't have rights. Only individuals in the community
 have rights. ... That idea of community rights is firmly rooted
 in the 'Communist Manifesto.'" -- Michael Badnarik