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Determining Which IP Address Db2 Connections are Connecting To

Determining Which IP Address Db2 Connections are Connecting To #ibmchampion

Database servers these days sometimes have a profusion of IP Addresses. IP V4, V6, management networks, and Virtual IP addresses all add to the ways applications connect in to a database server. I ran into an issue recently where I really needed to know what IP address was being used by an application, and thought I would share what I learned.

Information Needed

The output from the command used…

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DB2 Basics: What Port Number is Db2 Listening for Connections on?

DB2 Basics: What Port Number is Db2 Listening for Connections on? #ibmchampion

DB2 has one or two ports that it is listening on for each and every Db2 instance. Two Db2 instances cannot share a port to listen on. Remember that Db2 allows multiple instances per server and also multiple databases per instance, and has for years.

Determining the Port for a Db2 Instance

The port number used for Db2 connections is configured, and can be changed to meet varying requirements. It…

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DB2 Administrative SQL Cookbook: Listing Database Authorities that an ID/Group Holds

DB2 Administrative SQL Cookbook: Listing Database Authorities that an ID/Group Holds

Purpose

To list the database authorities held by an ID or group – authorities, not privileges. This information is not available in sysibmadm.privileges. The format of syscat.dbauth has columns with ‘Y’ or ‘N’ in them, and reading that quickly to answer the question “What permissions does this ID have?” can be a bit frustrating. This SQL could also be union-ed with SQL to query…

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IDUG North American Technical Conference 2018

IDUG North American Technical Conference 2018

Last year I crossed the line. The IDUG conference in Europe is now my favorite. But the North American technical conference is a very close second. Nowhere else can you get this level of detail and the contacts with IBMers and peers. I now get two favorite weeks a year!

Overview

The conference starts on Sunday, April 29th. This day has extra-cost Educational seminars, including a certification…

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RSCT APAR Affecting TSAMP

RSCT APAR Affecting TSAMP

Some of my clients, instead of engaging me for day-to-day support, engage me for expert assistance only when it all really hits the fan. This issue occurred for one of those clients, who had other support performing the HADR failovers while the Linux kernel was upgraded. The version of RedHat did not change, but the kernel did.

The kernel upgrade was entirely needed. Two servers of the four in an…

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Index of Introductory Db2 Topics

Index of Introductory Db2 Topics

This blog entry is designed to serve as a roadmap for current blog entries directed at those newer to Db2. In my mind, this likely includes anyone who has been working with Db2 for less than 2 years. However, often there are areas we spend more time in than others, so I think of these topics also as “spackle” – to fill in gaps for the self-taught. Note that some of the topics below are not links.…

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Db2 Basics: Error Messages

Db2 Basics: Error Messages

When I do work in other domains – even something as connected as scripting – I find the error messages confusing and unhelpful. Most of the time, this is mostly because I don’t know much about the language or the the area. I’d like to think that my opinion that Db2 error messages are really quite helpful and useful is unbiased, but having built a career on focusing on IBM Db2, I’m sure I am…

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Db2 Basics: Introduction to IBM Db2

Db2 Basics: Introduction to IBM Db2

What is Db2? This article is one of my few that is not directed at a Db2 DBA or someone trying to fill some of the roles of a Db2 DBA. This is directed, as much as I can manage, at any technologist trying to understand what Db2 is and the role it plays in an IT organization.

What is Db2?

Db2 is a Relational Database Management System(RDBMS). It organizes the storage of a vast array of types of…

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More on IBM's RFE Program for Db2 on LUW

More on IBM’s RFE Program for Db2 on LUW

Once IBM made the Request For Enhancement (RFE) program workable last year, I blogged about it and tweeted about it, but now that we’ve seen more action on it, I thought I’d share some additional details.

What is an RFE?

First off, an RFE is a request for some feature or functionality in Db2 that does not exist today. If you have ever opened a PMR, only to get a response that boils down to…

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Db2 Basics: Using FTPS to get a Fixpack Directly to a Db2 Server

This is the third time I have written this post. It keeps changing, so I keep sharing.

I work from home, so downloading software to my laptop and then uploading it to a server is not very efficient. Download speeds aren’t bad, but uploading can take 8 hours or more, depending on the client. This forces me, whenever possible, to move code directly to the server. The first time I wrote about this,…

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Db2 Basics: Investigating Permissions in an Existing Database

I have written several other articles on security and permissions, but I thought I would write one from a purely practical perspective. If you don’t understand the basics of how DB2 handles users, authentication, authorization, and privileges, please read Db2 Basics: Users, Authentication, and Authorization.

The Easiest Method

Back in the day, I worked as a peon-DBA in IBM Global Services. One of…

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High Availability Options for Db2 LUW

High Availability Options for Db2 LUW #IBMChampion

Why Should a Database be Highly Available?

It is significantly easier to implement high availability at other levels than it is at the database level. Often the database server is one of the more powerful servers in an environment, and without some fancy footwork there can be only one live copy of data. Ignoring high availability at the database level due to expense can be a bankruptcy-inducing…

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SQL1643C on Rollforward

I ran into this error message recently and thought I’d describe what the issue was.

The Scenario

I was building a new consolidated development database server for a client – moving away from 10 separate database servers to one (big) VM to run their development workloads. This was a Linux server, so I was setting INSTANCE_MEMORY to prevent any one instance from eating all the memory and to make it…

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The Self-Tuning Memory Manager (STMM)

Db2 memory management is a complex topic that I’ve already written about from several perspectives, and have a few blog entries in mind to explore further. A presentation that Melanie Stopfer gave a while back really helped me understand STMM better. I thought I would share what I learned.

What STMM Does

The Self-Tuning Memory Manger is a process that wakes up from time to time and reallocates…

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Reducing Contention: Changing Default Isolation Level for Websphere Commerce (WCS)

Reducing Contention: Changing Default Isolation Level for Websphere Commerce (WCS)

The Problem

I often lean on analogies when I speak to non-technical people about technical topics. For example, I would explain database locking as “two kids fighting for the same candy bar”.  If you introduce isolation levelsinto the conversation, I would expand the analogy to include “one sibling holding on to a candy bar they care nothing about just because they don’t want the other sibling…

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Establishing a DB2 JDBC Connection

Establishing a DB2 JDBC Connection

Recently I was forced outside my comfort zone and asked to vet various open source BI tools. I was a report developer in a past life, a database administrator supporting datamarts at various employers, and even supported Cognos backend databases. I thought my past experience gave me an edge when it came to evaluating BI tools.

I was immediately humbled when I had to create a simple JDBC…

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Avoiding Inoperative Tables on the HADR Standby

Avoiding Inoperative Tables on the HADR Standby

HADR does an awesome job of replicating all logged operations to 1-3 standby databases. It is remarkably simple to use and pretty resilient. More than once I’ve started talking to a client about PureScale only to discover their actual high availability and/or disaster recovery needs can easily be met by a 4-server HADR implementation. Sometimes even by a two-server implementation.

The Problem

The…