HA & Failover options

Hi all,

Let me give a brief background before i pose my questions:

Background:
We are currently working on the architectural phase of a program which
will involve implementing a given solution for multiple companies. We
have proposed to have physically separate organisation specific
instances for all the technology components (App Server, DB Server,
Security Infrastructure, Web Server, Infrastructure services for
Systems Management, Backup & Recovery). Major softwares used are Oracle
Application Server 10g Release 3 and Oracle Database Release 2. The
project has some strict HA & Failover requirements

The OS choices are AIX 5.2/5.3 and RedHat Linux 3/4. The box choices
are a) Commodity Servers: IBM x Series or HP ML/DI Series with Windows
2003 Server or Red Hat Enterprise Linux ES 3.0 or 4.0 b) Unix Server
IBM P570 Series with AIX 5.2 or AIX 5.3.

The HA software choices are IBM's HACMP/XD, Veritas Global Cluster
Software, RAC and Data Guard (DG), Oracle Application Server's
Clustering features.

Constraints:

a) We have historically not used RAC or DG or Oracle Application Server
Clustering in this shop
b) We have performed an exercise of aligning different technology
components. For instance, Database instance and Reports Server would
sit together in the same physical box, All infrastructure services
would sit in the same box
c)We have also made platform choices for all technology components
other than Application Server and Database Server


Questions:
a) For database which is the best cluster solution: HACMP/XD or VCGS or
RAC+Oracle Clusterware+Dataguard? I'm aware that in hardware based
clustering, the passive instance doesn't get used whereas in an Oracle
RAC solution it does get used. But i don't want to make use of
mid-range servers (p570 is one) along with Oracle RAC and a hardware
cluster since my cost shoots up. I would preferably use commodity
server clusters when deploying an Oracle RAC solution. Share your
thoughts on this. Also, how stable is Oracle clusterware? Please give
your estimation of the three options.

b)Do you have any large scale implementation experience of Oracle DB on
low end boxes such as IBM x Series/ HP ML/DI Series with either Windows
2003 Server or Red Hat Enterprise Linux ES 3.0 or 4.0? If yes, share
your experiences.

c) n+1 vs n+n

Currently we are proposing a 2*1 instance configuration across two
locations for the database based on it being a middle-path solution.
i.e., it is not exhorbitantly priced and at the same time it offers
reasonable failover and HA facilities. We are aware of the problems in
this option such as no protection from instance or node failures at the
secondary site, potential performance degradation at the secondary
site, manageability problems owing to asymmetric configurations across
primary and secondary sites

Can you provide your thoughts on n+n or n+1 configurations when dealing
with multiple database instances?

d) Generic vs Specific clustering solutions


Veritas Global Cluster Software has the advantage of being platform
independent whereas HACMP doesn't have. Does this factor ever play a
role in deciding the cluster software?

d) Cost

From a cost perspective out of the three options (IBM's HACMP/XD,
Veritas Global Cluster Software, RAC and Data Guard) which one is the
cheapest and which the costliest?

e) When using Data Guard is there a requirement for Global clustering
software or will the local clustering software itself perform the job?
Also, how instantaneous is failover to the secondary site with data
guard when failures occur in the primary site?

e) Data replication

For data replication across primary and secondary sites we have options
such as a) SAN or NAS based disk replication b) Data Guard. What are
the advantages/disadvantages in these two options?

f) Oracle Application Server

Historically we haven't used Application Server's clustering features
in this shop. For load balancing we have used Network Load balancers.
We didn't use Application Server's clustering features in the past
because the earlier releases of Oracle Application Server had some bugs
in this aspect. What is current status?

.

Relevant Pages

  • [NEWS] Multiple Vulnerabilities in Oracle Database (Character Conversion, Extproc, Password Disclosu
    ... The following security advisory is sent to the securiteam mailing list, and can be found at the SecuriTeam web site: http://www.securiteam.com ... Multiple vulnerabilities were discovered in the (Oracle database server ... password is required to exploit this vulnerability. ...
    (Securiteam)
  • Re: How to make your report run faster
    ... I've done no work with Oracle as the Server DB, ... > if they click the listbox then "Preview report" button is enabled. ... > -I was try to make the old queries for subreport, ...
    (microsoft.public.access.reports)
  • Re: I cant find a SETUP.EXE in the SQL Plus Client ??
    ... someone else's server for testing some SELECT statements I'm ... free client because I don't own the Oracle license. ... SQL statements. ... There is no documentation with that download. ...
    (comp.databases.oracle.tools)
  • RE: sunmanagers Digest, Vol 44, Issue 20
    ... diagnostics from the front-panel. ... Any ideas on what the problem may be or how to get this server powered ... The cluster itself is working, but I'm unable to shut down the nodes. ... Oracle uses shared memory for the communication between the client ...
    (SunManagers)
  • Re: I cant find a SETUP.EXE in the SQL Plus Client ??
    ... someone else's server for testing some SELECT statements I'm writing for them. ... How do I get a free Oracle client installed, if possible, so I can test some SQL statements. ... There is no documentation with that download. ...
    (comp.databases.oracle.tools)