Join IIUG
 for   
 

Informix News
18 Nov 13 - ZDNet - Top 20 mobile skills in demand... Read
09 Sep 13 - telecompaper - Shaspa and Tatung have shown a new smart home platform at Ifa in Berlin. Powered by the IBM Informix software... Read
06 Sep 13 - IBM data magazine - Mission Accomplished - Miami, Florida will be the backdrop for the 2014 IIUG Informix Conference... Read
01 Feb 13 - IBM Data Magazine - Are your database backups safe? Lester Knutsen (IBM Champion) writes about database back up safety using "archecker"... Read
14 Nov 12 - IBM - IBM's Big Data For Smart Grid Goes Live In Texas... Read
3 Oct 12 - The Financial - IBM and TransWorks Collaborate to Help Louisiana-Pacific Corporation Achieve Supply Chain Efficiency... Read
28 Aug 12 - techCLOUD9 - Splunk kicks up a SaaS Storm... Read
10 Aug 12 - businessCLOUD9 - Is this the other half of Cloud monitoring?... Read
3 Aug 12 - IBM data management - Supercharging the data warehouse while keeping costs down IBM Informix Warehouse Accelerator (IWA) delivers superior performance for in-memory analytics processing... Read
2 Aug 12 - channelbiz - Oninit Group launches Pay Per Pulse cloud-based service... Read
28 May 12 - Bloor - David Norfolk on the recent Informix benchmark "pretty impressive results"... Read
23 May 12 - DBTA - Informix Genero: A Way to Modernize Informix 4GL Applications... Read
9 Apr 12 - Mastering Data Management - Upping the Informix Ante: Advanced Data Tools... Read
22 Mar 12 - developerWorks - Optimizing Informix database access... Read
14 Mar 12 - BernieSpang.com - International Informix User Group set to meet in San Diego... Read
1 Mar 12 - IBM Data Management - IIUG Heads West for 2012 - Get ready for sun and sand in San Diego... Read
1 Mar 12 - IBM Data Management - Running Informix on Solid-State Drives.Speed Up Database Access... Read
26 Feb 12 - BernieSpan.com - Better results, lower cost for a broad set of new IBM clients and partners... Read
24 Feb 12 - developerWorks - Informix Warehouse Accelerator: Continuous Acceleration during Data Refresh... Read
6 Feb 12 - PRLOG - Informix port delivers unlimited database scalability for popular SaaS application ... Read
2 Feb 12 - developerWorks - Loading data with the IBM Informix TimeSeries Plug-in for Data Studio... Read
1 Feb 12 - developerWorks - 100 Tech Tips, #47: Log-in to Fix Central... Read
13 Jan 12 - MC Press online - Informix Dynamic Server Entices New Users with Free Production Edition ... Read
11 Jan 12 - Computerworld - Ecologic Analytics and Landis+Gyr -- Suitors Decide to Tie the Knot... Read
9 Jan 12 - planetIDS.com - DNS impact on Informix / Impacto do DNS no Informix... Read
8 Sep 11 - TMCnet.com - IBM Offers Database Solution to Enable Smart Meter Data Capture... Read
1 Aug 11 - IBM Data Management Magazine - IIUG user view: Happy 10th anniversary to IBM and Informix... Read
8 Jul 11 - Database Trends and Applications - Managing Time Series Data with Informix... Read
31 May 11 - Smart Grid - The meter data management pitfall utilities are overlooking... Read
27 May 11 - IBM Data Management Magazine - IIUG user view: Big data, big time ( Series data, warehouse acceleration, and 4GLs )... Read
16 May 11 - Business Wire - HiT Software Announces DBMoto for Enterprise Integration, Adds Informix. Log-based Change Data Capture... Read
21 Mar 11 - Yahoo! Finance - IBM and Cable&Wireless Worldwide Announce UK Smart Energy Cloud... Read
14 Mar 11 - MarketWatch - Fuzzy Logix and IBM Unveil In-Database Analytics for IBM Informix... Read
11 Mar 11 - InvestorPlace - It's Time to Give IBM Props: How many tech stocks are up 53% since the dot-com boom?... Read
9 Mar 11 - DBTA - Database Administration and the Goal of Diminishing Downtime... Read
2 Feb 11 - DBTAs - Informix 11.7 Flexible Grid Provides a Different Way of Looking at Database Servers... Read
27 Jan 11 - exactsolutions - Exact to Add Informix Support to Database Replay, SQL Monitoring Solutions... Read
25 Jan 11 - PR Newswire - Bank of China in the UK Works With IBM to Become a Smarter, Greener Bank... Read
12 Oct 10 - Database Trends and Applications - Informix 11.7: The Beginning of the Next Decade of IBM Informix... Read
20 Sep 10 - planetIDS.com - ITG analyst paper: Cost/Benefit case for IBM Informix as compared to Microsoft SQL Server... Read
20 Jul 10 - IBM Announcements - IBM Informix Choice Edition V11.50 helps deploy low-cost scalable and reliable solutions for Apple Macintosh and Microsoft Windows... Read
20 Jul 10 - IBM Announcements - Software withdrawal: Elite Support for Informix Ultimate-C Edition... Read
24 May 10 - eWeek Europe - IBM Supplies Database Tech For EU Smart Grid... Read
23 May 10 - SiliconIndia - IBM's smart metering system allows wise use of energy... Read
21 May 10 - CNET - IBM to help people monitor energy use... Read
20 May 10 - ebiz - IBM Teams With Hildebrand To Bring Smart Metering To Homes Across Britain... Read
19 May 10 - The New Blog Times - Misurare il consumo energetico: DEHEMS è pronto... Read
19 May 10 - ZDNet - IBM software in your home? Pact enables five-city smart meter pilot in Europe... Read
17 March 10 - ZDNet (blog) David Morgenstern - TCO: New research finds Macs in the enterprise easier, cheaper to manage than... Read
17 March 2010 - Virtualization Review - ...key components of Big Blue's platform to the commercial cloud such as its WebSphere suite of application ser vers and its DB2 and Informix databases... Read
10 February 2010 - The Wall Street Journal - International Business Machines is expanding an initiative to win over students and professors on its products. How do they lure the college crowd?... Read


End of Support Dates

IIUG on Facebook IIUG on Twitter

[ View Thread ] [ Post Response ] [ Return to Index ] [ Read Prev Msg ] [ Read Next Msg ]

IDS Forum

Re: Ontape/logical logs

Posted By: Martin Fuerderer
Date: Thursday, 30 September 2004, at 5:54 a.m.

In Response To: Ontape/logical logs (Peter Skipworth)

Hi,

no, you are not. You can let the running "ontape -r" command apply
as many logs as you want (or have), but once it has finished there is
no way to start applying logs again.
The reason for this is, at the point where you tell the "ontape -r"
command that you have no more logical logs, the database is
(at least generally) in an inconsistent state. That means there will be
some open transactions. With no more logs available (as you told
the "ontape -r" that there are no more logs), there is "no hope" that
these transactions will ever be committed. To avoid that these
transactions stay open for the remaining eternety, they are rolled
back. This is the so-called "transaction clean-up phase" of the restore.
Now the database is logically consistent.
Applying new log files would mean that you would want to continue
where you were before the "transaction clean-up", i.e. you would want
to continue those open transactions. But as they have already been
rolled back, there's no way to continue them. Therefore it's not
possible to apply more logical logs after a restore has finished.

You can split the restore into the physical restore ("ontape -p")
followed by the logical restore ("ontape -l") but the same applies,
as soon as you have finished that "ontape -l" command there was
a "transaction clean-up" and no return to log applying is possible.

Having said all this, it becomes clear that Norma Jean Sebastian
is absolutely correct (as always :) , because HDR (High-availability
Data Replication) is doing exactly what you are trying to achieve
manually. It keeps the secondary server (the slave) in this "log
recovery phase", i.e. after a physical restore (and possibly restoring
some logical logs from tape) it will not do the "transaction clean-up".
Instead it will always wait for new logical log records to arrive so that
they can be applied. This is done automatically, i.e. the primary (master)
and secondary server "talk to each other" to figure out, when log
records are to be transfered from primary to secondary and applied
there. This is ongoing at the discretion of transactions, rather than
a whole log file at the time it becomes full. So it gives you a hot
standby that is much more up-to-date. It also gives you the
added benefit that you can still use this secondary server for
querying data (obviously you can't modify data on the slave).

There's more benefit to gain, so I recommend reading the
manual "Administrator's Guide", especially the chapter
about "High-Availability Data Replication".

Regards,
Martin
--
Martin Fuerderer
IBM Informix Development Munich
Data Management Solutions

forum.subscriber@iiug.org wrote on 30.09.2004 02:21:09:

> Hi all,
>
> I'm reasonably new when it comes to Informix, so I hope this isn't an
often-
> asked question. I've set up a disaster recovery server for our main
Informix
> server, to which I automatically send my level 0/level 1 backups and
logical
> logs, as they're written to disk. I've performed a restore with 'ontape
-r'
> successfully, but have a question. Once I finish performing the ontape
> command, am I able to apply each logical log in turn, as it's sent to
the
> backup server, to bring it up to date ? I thought 'ontape -l' might be
what
> I
> needed, but it doesn't seem to work...
>
> I realise 'ontape -r' is able to apply logical logs, but I'd obviously
> prefer
> not to have to restore the entire database if we ever have a severe
crash.
>
> Any help appreciated,
>
> Cheers,
>
> Peter

Messages In This Thread

  • Ontape/logical logs
    Peter Skipworth -- Wednesday, 29 September 2004, at 8:21 p.m.
    • RE: Ontape/logical logs
      Sebastian, Norma J. -- Wednesday, 29 September 2004, at 11:37 p.m.
    • Re: Ontape/logical logs
      Martin Fuerderer -- Thursday, 30 September 2004, at 5:54 a.m.

[ View Thread ] [ Post Response ] [ Return to Index ] [ Read Prev Msg ] [ Read Next Msg ]

IDS Forum is maintained by Administrator with WebBBS 5.12.