[LU-3106] create symlinks in procfs from ofd to osd

• Type: Improvement
• Resolution: Fixed
• Priority: Critical
• Fix Version/s: Lustre 2.4.0
• Affects Version/s: Lustre 2.4.1
• Assignee: Alex Zhuravlev
• Reporter: Alex Zhuravlev

Description

to preserve compatibility with pre-2.4 versions we should create few symlinks from /proc/fs/lustre/obdfilter/*/ to the corresponded OSD.
namely these are writethrough_cache_enable, readcache_max_filesize and read_cache_enable.
this way all the utilities (including 3rd party) keep working and the documentation is still valid.

Issue Links

• is duplicated by: LU-3300 Restore missing proc information for LMT