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Oracle 12c: ASMLib vs. UDEV on RHEL7

Michael8773Oct 20 2016 — edited Oct 23 2016

Hello,

In scouring the Internet I have encounter mixed messages on this topic.  Ideally on RHEL 7 (Redhat version 7) I want to use just ASMLib rather than having to mess with udev (yuck!!!!).  Most current examples however seem to say "yes use ASMLib" but then still go on and perform udev operations!?  Some examples: 1, 2, 3

With respect to ASM\RAC\disks, udev seems to minimally require:

  • Identifying the disks (/sbin/scsi_id)
  • Getting the output for every disk (Example: /usr/lib/udev/scsi_id -g -u -d /dev/sdb1 ==> 1ATA_VBOX_HARDDISK_VBbaffce72-62c14e41).
  • Creating a custom rules file (/etc/udev/rules.d/90-ib.rules).

My questions:

  1. Is ASMLib designed such that you do not need to perform udev operations to configure disks for ASM?
  2. Is ASMLib fully supported on RHEL 7 for ASM and  RAC?

Thanks for clarifying this,

Michael

Comments

alwu-Oracle
What is your DB version and what version of Jena Adaptor are you using?

Thanks,

Zhe Wu
Ram Krishna
The oracle database is v11.1.0.7 and we are using the new Jena adaptor (rel 3) that we got from our metalink site.

ram
alwu-Oracle
Hi,

It seems that the new version of Jena Adaptor is doing the right job to convert the whole SPARQL into a single SEM_MATCH based query. Now the problem is that 11.1.0.7 database has this known server side bug (table function related) when the query is too big. You did not see this problem with Jena Adaptor v2 because ARQ breaks the query into many small pieces.

To fix this problem, there are a few choices:

1) upgrade to database 11.2, or
2) shorten your query, or
3) file a tar with Oracle support.

We are working on an optimization in Jena Adaptor to convert a SPARQL (with just a base BGP and a number of parallel OPTIONAL clauses) into a plain SQL. This may solve your problem even if you continue use 11.1.0.7.

Cheers,

Zhe Wu
1 person found this helpful
Ram Krishna
Thanks Zhe- that is helpful. We will use one of the workarounds before we switch to 11.2.

ram
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Post Details

Locked on Nov 20 2016
Added on Oct 20 2016
#asm, #performance-availability, #rac-asm-clusterware-installation
9 comments
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