Blog has been renamed!

Posted by David Yahalom under General IT

As you probably noticed I’ve changed my blog’s name and URL to www.davidyahalom.com instead of www.authoritybase.com. After doing some thinking I’ve decided that it is more appropriate for my blog at its current stage to reflect my name instead of using something more original. You can still access it by typing www.authoritybase.com, but all new articles and views will be published under the www.davidyahalom.com domain.

I’ve also created a new logo for my blog, one that better reflects the database related content on this site.

Proactive monitoring with Oracle Grid Control

Posted by David Yahalom under ITIL, Grid Control, Monitoring, General IT, Oracle

Data centers today are becoming huge and complex. There’s a definite need to provide 24/7, always-on, high SLA services. The sheer maintenance of such complex environments can be a daunting task for any IT staff.As the complexity of systems increases, the need for better, more comprehensive monitoring solutions becomes more critical. The monitoring tools and methodologies that were once considered good-enough just don’t cut it anymore.

Knowing that servers are up and running and that the backups have finished successfully isn’t enough. Complex systems require complex monitoring methodologies taking into account complex SLAs scenarios that usually span dozens of servers and tens of connected systems.

There are two methodologies for troubleshooting system performance. You can be reactive – wait for the problems to happen and then do your best to solve them as fast as you can or be proactive – learn of potential problems and bottlenecks before they become critical and affect your business.

Being proactive has many advantages including minimizing downtime and freeing your IT staff to advance future projects rather then put out fires all day long. In the IT world staying in one place is pretty much the same as going backward.

The proactive approach is derived from identifying problems before they happen and addressing them before they become a problem for your company. You can define a set of rules, either application based rules or system based rules which will be defined as the SLA indicator for the application. These rules can be anything from “page load time” to system-oriented tests such as CPU load or blocking sessions to a combination of both. Being proactive means being alerted once the load time for a certain page in the application has exceeded a predefined threshold.

Grid Control is Oracle’s high-end, fully fledged, enterprise-wide, monitoring and management solution. Grid Control is a single, integrated solution for administering, operating and monitoring applications and systems.

While Grid Control provides has the most complete set of Oracle Database monitoring metrics from any other tool on the market today, it can also do much more as a monitoring solution beside monitor Oracle Databases only.

Grid Control provides the following capabilities and features:

1) Application Management.

2) Database Management.

3) Middleware management.

4) Real User Experience insight

5) Host / Server management

6) SOA management

7) Identity management.

Each of these features consist of both predefined metrics for evaluating system performance and availability plus the ability to create custom metrics handing over control on what specifically Grid Control monitors to you. You have the capability to group several key systems together and define a service group that is dependent on the availability and performance of all the targets belonging to that service group.

Grid Control allows for self-tuned and self managed databases, automation of complex or routine manual tasks which are often error-prone, rapid root cause analysis through established standards and complete compliance enforcement.

Using the combination of Grid Control and Oracle 10g’s ADDM feature you can periodically examines the state of the database, automatically identify potential bottlenecks and have Grid Control recommend corrective actions.

Oracle Enterprise Manager presents ADDM findings and recommendations in a convenient and intuitive fashion and guides administrators in step-by-step process to quickly resolve performance problems by implementing ADDM recommendations.

Grid Control also offers a large array of compliance assessments (with out-of-box included policies), security violation reports, patch advisories, multiple-target deployment and of course – alerts. You can have Grid Control notify you of potential problems both via email, SMS text messages and SNMP traps.

 Using GridControl for ITIL compliance

This last section of the article can be crucial to some of you looking for ITIL compliance. ITIL stands for IT Infrastructure Library - a widely accepted approach and methodologies to IT service management providing a complete and comprehensive set of best practice guidebooks supported by a qualifications scheme, training and implementation and assessment tools. ITIL was designed to promote the quality of computer services in the organization and provides management with a template framework for best practices to achieve quality IT services and overcome difficulties associated with the growth of IT systems. ITIL is divided into a set of text books, qualification programs, software tools and user groups slicing the services expected from an IT department:

1. Service support.

2. Service delivery.

3. Managerial.

4. Software support.

5. Computer operations.

6. Security management.

7. Environmental

So how exactly can Grid Control help you become ITIL certified?

Since Grid Control can essentially monitor everything in your DataCenter it can better help you align business aspects with your IT aspects.

 

ITIL configuration management

The basic process defined by ITIL is that of configuration management. This is essential for both service support and service delivery.

Configuration management means tracking all of the individual hardware components supporting your business IT infrastructure and all of the changes these components undertake. Grid Control tracks all of these changes in a build-in Configuration Management DB (or CMDB for short) which keeps all history data easily accessible using Grid Control’s interface.

Each one of these Configuration Items is linkable to other Configuration Items in your infrastructure. You can define a connection between servers X,Y,Z and the organization HR system. Grid Control also has the ability to automatically identify the relation between separate configuration items and greatly reduce the overhead with manually documenting and linking individual configuration items.

This allows the developer to notify the system administrator that ever since he replaced the network card in the production server the entire application is running slower than usual. Identify the change that caused the problem.

  

ITIL Problem management

Another key ITIL process is the diagnostic of reoccurring problems and failures. Reoccurring errors are usually a sign of problems that were poorly handled when they first occurred. Grid Control allows us to identify the error when it happens by using root cause analysis, helping us identify the underlying problematic configuration item thus greatly simplifying troubleshooting.

ITIL Change management

Change management in complex IT environments is all about they way your IT staff can coordinate changes in your infrastructure so that they can easily identify which systems are being affected by the proposed change. Grid Control automatically documents any change made in your business IT infrastructure. By creating “baseline snapshots” using Grid Control you can later compare your infrastructure configuration to a given point in time.

Grid Control also supports Change Automation allowing us to schedule automatic deployment of Oracle patches.

 

ITIL Release Management

ITIL release management is the ability to release final, production-grade synchronized versions of your IT system along with all of its configuration items corresponding to the various installation procedures and regulations in place.

This gives us the ability to keep a “closed” version of our configuration management (combination of hardware, O/S choice, DB version…) as a standby baseline and use this baseline to easily make future copies. Grid Control fully supports ITIL release management by allowing us to automate our deployment procedures of the entire system from the bare-metal upwards.

ITIL Capacity Management

Since both system load and capacity play critical roles in the availability and performance of your business systems, ITIL defines a process to easily manage and quantify your systems capacities. In order to predict the capacity required to support future workloads, Grid Control tracks the system performance over a period of time allowing you to slice the performance by various indicators such as user activity.

This is just a quick tour of Grid Control and really, only a drop in the sea in terms of capabilities and options at your disposal. We strongly recommend that you install Grid Control for yourself and explore the world of proactive, smart IT infrastructure monitoring and management. 

And remember…. Once you go Grid, you’ll never go back!

 

Started a new job!

Posted by David Yahalom under General IT

Pop up the champagne bottles people!

I have started a new job as a Senior Project Manager at the Veracity Group , the leading Oracle Consulting group in Israel. Veracity is the only Oracle certified Value Added Distributor (VAD) in Israel and part of a very small and exclusive list of Oracle VADs around the world. Our customers benefit from the unique advantage we offer of both directly licensing and selling Oracle products as well as having an outstanding expert Professional Services team. We’re Simply the best in our field, trust me. As part of my new job at Veracity, I’m also holding the CTO title of a very special group in the Oracle Database development business, but more on this later.

I’ve been able to accomplish a great deal in the last six years as a database consultant, especially during my time at Xpert-One1 which was a very rewarding experience. For some time now I’ve been looking into getting a more managerial position and when the opportunity presented itself, I simply couldn’t resist. My new position puts me directly in the middle decision making process about all things technological - so I think this would make a great learning experience for me. I’m still (and always will be) a bits and bytes kind of guy so I’m looking forward combining my deep passion for technology with having a managerial position. Any tips on how to exactly accomplish this from all you veterans out there are welcome!

Simulate load on your linux server using a one-liner

Posted by David Yahalom under Unix, Linux, General IT

Yesterday I needed a quick way to simulate load on a Linux sever. I wanted to find out that my monitoring system is working and sending alerts.

While there are many many tools that can do this, all I needed was a simple bash one-liner shell script that can make the CPUs beg for mercy.

What I ended up using is this:

dd if=/dev/zero bs=100M | gzip | gzip -d | gzip | gzip -d | gzip | gzip -d > /dev/null &

Send a few of these babies to the background and you’ll start seeing smoke coming from your server soon enough.

Oracle Virtual Directory

Posted by David Yahalom under ETL, General IT, Oracle

Another presentation I’ve made not too long ago at an Israel Oracle User Group meeting (sponsored in part by Xpert-One1, the consulting and solution provider company I work for) was about a relatively little known product (at least by Oracle terms) called Oracle Virtual Directory.

OVD allows for Enterprise Level LDAP without synchronization.

Oracle Virtual Directory provides LDAP and XML views of existing enterprise identity information without synchronizing or moving data from its native locations.

OVD can connect to pretty much anything JAVA can connect to and expose several different LDAP directories and RDMBS data repositories as a single LDAP tree.

Think about it. You can virtually “unify” all the different directories in your organizations (be it RDBMS servers or LDAP directories) as a single directory service - which is so much easier to work with. And without any sort of synchronization.

Very very cool.

You can get my presentation here.

OVD is availiable for download, free, from OTN. 

Misc tip: search for all unread mail in Gmail

Posted by David Yahalom under General IT

For ages I’ve looked for a way to quick search for all unread mail in Gmail.

I need this because most of the time I let a few unimportant (read: advertisements) emails slip by me without reading them or marking them as read. After time, this list grows and I find it annoying to always receive notifications as if I have unread mail in my inbox (I have unread mail, it is just unimportant mail I forgot to mark as read).

Well, there doesn’t seem to be a way to search for only unread mail using Gmail’s interface but there is quick way around this.

Just type:

is:unread

Into the search box!

Oracle extent allocation: AUTOALLOCATE vs. UNIFORM

Posted by David Yahalom under General IT

Starting with Oracle 9i, DBAs can now create locally managed tablespaces.

A Locally Managed TBS manages its own list of free extents in a bitmap block placed inside the header of the first data file of the tablespace. Inside the bitmap block, each bit maps to a free block in the tablespace.

When creating a locally managed tablespace, you can specify the extent allocation method to be used.

AUTOALLOCATE - means that the extent sizes are managed by Oracle.
Oracle will choose the optimal next size for the extents starting with 64KB. As the segments grow and more extents are needed, Oracle will start allocating larger and larger sizes ranging from 1Mb to eventually 64Mb extents. This might help conserve space but will lead to fragmentation. This is usually recommended for small tables or in low managed systems.

UNIFORM - specifies that the extent allocation in the tablespace is in a fixed uniform size. The extent size can be specified in M or K. The default size for UNIFORM extent allocation is 1M. Using uniform extents usually minimizes fragmentation and leads to better overall performance.

SQL>CREATE TABLESPACE test_tablespcae DATAFILE '/emc/oradata/test_tablespace1.dbf' SIZE 50M
EXTENT MANAGEMENT LOCAL AUTOALLOCATE;

SQL>CREATE TABLESPACE test_tablespcae DATAFILE '/emc/oradata/test_tablespace1.dbf' SIZE 50M
EXTENT MANAGEMENT LOCAL UNIFORM SIZE 512K;

I usually prefer to keep large production-grade tables in UNIFORM sized tablespaces and smaller tables or tables in unmanaged environments in AUTOALLOCATE tablespaces.