External References, Backlink and Obituaries Check
When a server references an object that it does not have locally, an external reference to that object is created, and the object will have a DRL (Distributed Reference Link) to the server that holds its exref. It is a good idea to know how many external references a server holds, if there are many then the server should hold a copy of the replica. This check will also show any obituaries and their state.
For Solaris or Linux execute ndsrepair –C – login as root required Total errors reported should be 0, investigate any errors shown.
To include obits reporting execute ndsrepair –Ad –C
After this has been run the log file shows exrefs that are backlinked (DRL) and lists any obituaries that have not yet completed. Of primary concern are the obituaries that have not completed. For example, problems can emerge if the obituary flag remains in the same state and is never purged. This condition indicates a possible communication problem between servers or that a server may have been removed, or crashed, improperly.
If you suspect backlink, exref and obit problems then use ndstrace to check.
The procedure for doing this is:
set ndstrace = on
set ndstrace = nodebug
set ndstrace = +blnk (Enables backlink messages)
set ndstrace = +bldt (Enables detailed backlink messages)
set ndstrace = +jntr (Enables Janitor messages)
set ndstrace = *b (Forces Backlink to run)
set ndstrace = *f (Forces the Flat Cleaner to run)
The displayed information is saved automatically in the /var/nds/ndstrace.log file, which can be viewed through a text editor.
When a server references an object that it does not have locally, an external reference to that object is created, and the object will have a DRL (Distributed Reference Link) to the server that holds its exref. It is a good idea to know how many external references a server holds, if there are many then the server should hold a copy of the replica. This check will also show any obituaries and their state.
For Solaris or Linux execute ndsrepair –C – login as root required Total errors reported should be 0, investigate any errors shown.
To include obits reporting execute ndsrepair –Ad –C
After this has been run the log file shows exrefs that are backlinked (DRL) and lists any obituaries that have not yet completed. Of primary concern are the obituaries that have not completed. For example, problems can emerge if the obituary flag remains in the same state and is never purged. This condition indicates a possible communication problem between servers or that a server may have been removed, or crashed, improperly.
If you suspect backlink, exref and obit problems then use ndstrace to check.
The procedure for doing this is:
set ndstrace = on
set ndstrace = nodebug
set ndstrace = +blnk (Enables backlink messages)
set ndstrace = +bldt (Enables detailed backlink messages)
set ndstrace = +jntr (Enables Janitor messages)
set ndstrace = *b (Forces Backlink to run)
set ndstrace = *f (Forces the Flat Cleaner to run)
The displayed information is saved automatically in the /var/nds/ndstrace.log file, which can be viewed through a text editor.
No comments:
Post a Comment