Jason L. Froebe, Perot Systems, Team Sybasehttp://www.froebe.netjason@froebe.netOctober 2004

Adaptive Server Enterprise

Migration to Linux

Adaptive Server Enterprise

Agenda

• Why Migrate to Linux?

• Steps in Migrating

Prepare target Linux System & install ASE

Migrate server structure

Migrate the databases

Validate migrated data, stored procedures and application

queries

• Customer Case Study

mLogica, Inc. and SubscriberMail – ASE on Linux Migration

Why Migrate to Linux

• Linux brings seductive Intel economics into the UNIX

heart of the datacenter

• Lower licensing costs compared to the UNIX variants or

Microsoft Windows 200x

• Linux allows shift from RISC-based servers running

proprietary UNIX systems to lower cost Intel-based

systems—without sacrificing dependability

Agenda

• Why Migrate to Linux

• Steps in Migrating

Prepare target Linux system & install ASE

Migrate server structure

Migrate the databases

Validate migrated data, stored procedures and application

queries

• Customer Case Studies

mLogica, Inc. and SubscriberMail – ASE on Linux Migration

Preparing the Server and Installing ASE

• Check O/S version and patches

• Create a Sybase account

• Adjust Shared Memory Segment

• Create Raw Partitions

• Install ASE

Migrate Server

• Moving the server is easy:

Allocate storage space for databases on the new ASE

• Create devices for the data areas

Create the DB

Set options using sp_dboption

Migrate the Database Structure and Data

Multiple methods including Sybase, 3rd Party & Open Source Tools

• Sybase Tools

Bulk Copy

SybMigrate

PowerTransfer

Replication Server

SQL Remote

Cross-platform Dump and Load

• 3rd Party Tools

BMC SQL Backtrack

• Open Source Tools

Scott Grey's SQSH

Michael Peppler's DBI DBD::Sybase, Simple:Sybase, BCP Tool

Migrate the Database — BCP

• Bulk Copy (bcp) and DEFNCOPY

Benefits:

• Most reliable

• Can be very fast compared to other solutions

Drawbacks:

• Requires intermediate files for the transfer. No SERVER to

SERVER transfers1

• Data fields may contain the delimiter used causing the bcp

in to fail

• Command line based

– Many people are uncomfortable with non-GUI

based tools

1Server to Server transfers can be obtained by using a named pipe on UNIX, Linux servers.

• SybMigrate

Overview:

• Java based program designed to migrate 2K pages to otherpage sizes

• Integrates the features of bcp and defncopy to 'migrate' onedatabase to another. Not necessarily on the same platform

Benefits:

• One of the easiest methods of moving a database from oneserver to another

Drawbacks:

• Requires Java to be installed

• Works on ASE 12.0.x and higher (included in ASE v12.5.3)and higher only

• May be necessary to run multiple times on the samedatabase as not all nested objects may be transferred onthe first try

• Slower than dump/load or defncopy/bcp

Migrate the Database — SybMigrate

Migrate the Database — Replication Server

• Replication Server

Benefits

• Relatively fast for keeping the data synced on multiple

platforms

• Replication Server 12.6 can replicate an entire database

from one machine to the other in a single Replication

Definition

Drawbacks:

• Overkill for one time migrations

• Expensive for casual use

• High learning curve

• Table definitions still must be transferred manually or with

defncopy

• Initial synchronization of the databases is slow

Migrate the Database — Power Transfer

• Overview Transfers data from a wide variety of sources into Sybase ASE

Useful for ASE to ASE migrations when architecture is differentand dump files cannot be loaded

• Benefits GUI based interface appeals to point & click

Cross DBMS vendor migrations

• Drawbacks Slowest of all migration tools

Dependence on Microsoft Windows as the transfer

• Read from UNIX

• Write to Linux

• Massive network I/O

Better suited for DBMS to DBMS migrations rather thanSybase to Sybase migrations

Cross-Platform Dump & Load

• Benefits

Allows easy migration from 11.9.2x or 12.x to 12.5.3 orhigher servers

Source Sybase ASE server does not need to be running on thesame operating system as the target Sybase ASE server

Least amount of DBA work needed for migration

• Drawbacks

Source & Target page size must be the same

Target must be 12.5.3 or higher

Takes only 2.5–3.5 times compared to a normal load databasedue to the conversion of the objects

Drop and recreate non-unique indexes including those onsystem tables

• Index recreation of system tables is performed by using'dbcc reindex'

• Constraints resulting in indexes would also have to berecreated

Cross-Platform Dump & Load

Source must be in a transactionally quiescent state

• No open transactions

• No log records that need processing at load time

• Note that you cannot use the quiesce database command as

it blocks dump database

• Replication must be disabled

• The recommended way to quiet the database:

Put DB in single user mode

run sp_flushstats and wait for pages to be flushed

truncate the log

checkpoint the database

dump database

If upgrading from an earlier version (pre 12.5.3), binary

only stored procedures will have to be reloaded

Migrate the Database — Third Party Tools

• BMC SQL-BackTrack (logical dump/load)

Overview

• An alternative quasi platform independent dump & load

product from BMC

• Extracts the table/index definitions and the data

• Recreates the tables & indexes on the target database

• Loads the data

Benefits

• Relatively simple interface

• Some companies already use BMC for their data recovery

needs so this would be a simple operation

Drawbacks

• An add-on license from BMC

• Very slow

Migrate the Database — Open Source Tools

• Scott Grey's SQSH

http://www.sqsh.org

Supports SERVER to SERVER bulk copy

Latest version supports the new data types in 12.5

Not actively updated

• Michael Peppler's DBI DBD::Sybase

Uses Perl's DBI mechanism for quasi-generalized access toSybase ASE

DBD::Sybase 1.04.6 (test release) includes support for thebulk API

Very easy to use

• Michael Peppler's Simple::Sybase

• Michael Peppler's SybPerl

Most popular Perl module for accessing Sybase databases

Migrating Stored Procedures

• There are no known issues if you have the source for the

stored procedures available

• If the source of the stored procedures is not available:

You will need to contact the 3rd party that you obtained the

stored procedures

If the source is not available from any location, you will need to

try to reverse engineer them. This can be a long and involved

process

Users & Passwords

• master..syslogins.password column uses a one way hash

• The hash is platform specific

Use Trace Flag 1650 for ASE on Linux 12.5.1+ to read ASE on

Sun Solaris syslogins

• Covered under CR #324847:

Passwords from Solaris 32-bit/64-bit can be migrated to Linux

using BCP or other data migration tools and used as such.

Trace flag 1650 will turn on the compatibility mode. This

compatibility mode is available only on Linux platform and only

passwords from Solaris 32-bit/64-bit can be migrated.

• Use LDAP user authentication instead of migrating

master..syslogins. See the slide “A Quick Low-Down on

LDAP User Authentication”

• The encryption of the passwords may change in a future

release

Quite possibly a platform independent encryption scheme finally

eliminating the cross platform passwords nightmare

How to Handle LDAP UA in Migration

• Hybrid mode: If user does not exist in LDAP server, useinfo in master..syslogins

Optionally update master..syslogins with info from LDAP server

• Exclusive mode: If user does not exist in LDAP server,

deny login

• A word of warning: The connection between ASE and the

LDAP server is unencrypted

LDAP records are transmitted in clear-text across the network.

Depending on your environment, this may be a security issue1

Workarounds:

• Encrypt the connection manually by using SSH Tunneling

(or similar)

• Place the LDAP server on the same machine as ASE

ASE should connect to the LOCALHOST, port to the

LDAP server

1 If it is a security issue for your environment, please inform Sybase.

Validate Migration

• Validate migrated data, stored procedures and

application queries

Use standardized scripts to perform logical data integrity

checks

Test stored procedures & application SQL to ensure execution

is identical

Test all clients for acceptable performance

• Test

User Interface

Batch Processing

Administration Procedures

Disaster Recovery

Application Performance

• Run the old and new ASE servers in parallel in case of

the need to migrate back

Migrating to Linux — Things to Keep in Mind

• Moving the data and the definitions is easy

• The real problems are not with the Linux port ofSybase ASE

• Things to watch out for:

Shell script differences

• Return codes may be different

• Shell script tricks on Solaris, AIX, HPUX, etc. may not workexactly as on their open source equivalents (BASH, tcsh,pdksh, etc.)

The infamous GNU C Library (GLIBC)

• The GLIBC has had a history of not being 100% backwardcompatible

• Sybase, Oracle, IBM, Sun and others have been bitten byslight behavior changes by either the GLIBC maintainers orthe various distributions

• Remember RedHat breaking the ASE with a customizedGLIBC patch in RedHat Linux version 9? Once discovered,RedHat quickly fixed the patch in a later customized release ofthe GLIBC

Device drivers• Specifically with drivers for SAN and Baydel disk arrays

• Many of the enterprise storage system providers are relativelynew to Linux

• Their drivers may work in their labs under low or medium loadsbut you may discover flaws under heavy and/or sustainedusage

• Do not use the BCM5700 LAN/NIC driver from Broadcom. Ithas several severe bugs that have yet to be resolved

• Use the community developed and supported TG3 driverfor the Broadcom 5700 network cards

• Broadcom bcm5700 has more features but the TG3 driveris far more stable

Blades• Benefits

• Reduces need of valuable space in the computer room

• Lower cost in theory

• Drawbacks• Heat dissipation while all blades are in heavy use

• Shared network, disk I/O can be bottlenecks

• Lock into a single hardware vendor

Migrating to Linux — Things to Keep in Mind

Case Studies — Successful Migrations to Linux

Mr. Amit Okhandiar

President,

mLogica, Inc.

Case Studies — Successful Migrations to Linux, Background

• Systems Integrator: mLogica, Inc.

• Client: SubscriberMail – Naperville, IL

Old System – Microsoft SQL Server on Windows NT

New System – Sybase ASE on Linux

Business: e-Mail marketing tools and services

Clients: Apple, AC Nielsen, American Marketing

Association, Chicago Bulls, etc.

• Business Drivers

Rapid growth in business

High volume of transactions

Database corruption

System instability

Lack of scalability

• Scalability

• Performance of the database transactions and queries

• CPU Utilization

• Memory Utilization

• I/O Performance

• DB sizing planned to predict system growth

• Highly configurable for the convenience of the application

• Technical Drivers

Performance

Scalability

Security

Cost

Flexibility

Manageability

Case Studies — Successful Migrations to Linux, Challenges

• Analysis of the current environment

• P&T and stabilization of the current environment

• Migration Planning

• Parallel Run

• Production Cutover

• Implementation

RAID 10 – Taking advantage of…

• Throughput of multiple spindles

• Redundancy of mirrored drives

• Automatic load balancing

Case Studies — Successful Migrations to Linux, Process

More Information

• ASE on Linux FAQ

http://www.peppler.org/FAQ/linux.html

• ISUG

Sybase FAQ http://www.isug.com/Sybase_FAQ

ISUG Journal 3rd Quarter 2003 (PowerTransfer)

• Sybase

Newsgroups http://forums.sybase.com

ASE Migration to Linux White Paper

http://www.sybase.com/content/1025612/ASE_Linux_Migration_

wp.pdf

Linux Migration Training

http://www.sybase.com/detail?id=1026016

• Sybase SDN

• Register today for the Sybase Developer Networkhttp://www.sybase.com/sdn