to check that the oracle user has been added and to verify permissions. You can edit the files with the vi editor or another text editor. > cat /etc/security/limits.conf #<domain> <type> <item> <value> # oracle soft nproc 2047 oracle hard nproc 16384 oracle soft nofile 1024 oracle hard nofile 65536 # End of file > cat /etc/pam.d/login #%PAM-1.0 auth [user_unknown=ignore success=ok ignore=ignore default=bad] pam_security.so auth include system-auth account required pam_nologin.so account include system-auth password include system-auth # pam_selinux.so close should be the first session rule session required pam_selinux.so close session include system-auth session required pam_loginuid.so session optional pam_console.so # pam_selinux.so open should only be followed by sessions to be executed in the user context session required pam_selinux.so open session optional pam_keyinit.so force revoke session required /lib/security/pam-limits.so session required pam_limits.so Some system areas, such as those listed for the parameter and option settings, can normally be viewed but not modified. Administrator permissions (root access) might be needed to make changes to these files. If sharing the server with another application, it’s important to make sure that changes to these system areas are communicated, or discussed first. Even without write permissions, having access to this information is helpful for doing a comparison of what is needed and being able to communicate what configuration changes are needed to the server administrator. 52 Oracle Database Administration for Microsoft SQL Server DBAs Other Linux Considerations Filling up some shared areas, such as /tmp, will cause issues with running or installing Oracle software. You should be careful about placing files in these areas and be sure to purge any old installation logs that are placed there. Required Packages The Oracle installation guide lists the required packages for the various Linux flavors. Some of the packages will already exist on your system, since they are included in the Linux installation. You should verify that they were installed by using the command rpm –q package_name. You will need to install any of the required packages that have not been installed by default. As an example, for Red Hat or Oracle Enterprise Linux 5.2 and Oracle Database 11 g Release 2 (R2), the following required packages are included in the Linux installation by default (verified by using rpm with the –q option): binutils-2.17.50.0.6-6.el5 (x86_64) compat-libstdc++-33-3.2.3-61 (x86_64) compat-libstdc++33-3.2.3.61 (i386) elfutils-libelf-9.125-3.el5 (x86_64) glibc-2.5-24 (x86_64) glibc-2.5-24 (i686) glibc-common-2.5-24 (x86_64) ksh-20060214-1.7 (x86_64) libaio-0.3.106-3.2 (x86_64) libaio-0.3.106-3.2 (i386) libgcc-4.1.2-42.el5 (i386) libgcc-4.1.2-42.el5 (x86_64) libstdc++-4.1.2-42.el5 (x86_64) libstdc++-4.1.2-42.el5 (i386) make-3.81-3.el5 (x86_64) If there are 32-bit and 64-bit versions listed, it doesn’t matter whether you are running on a 32-bit or 64-bit version—both must be installed. Continuing with the same example, the following required packages are not installed by default and will need to be added: elfutils-libelf-devel-0.125-3.el5.x86_64.rpm elfutils-libelf-devel-static-0.125-3.el5.x86_64.rpm elfutils-libelf-devel and elfutils-libelf-devel-static static-0.125-3.el5.x86_64.rpm glibc-headers-2.5-24.x86_64.rpm kernel-headers-2.6.18-92.el5.x86_64.rpm glibc-devel-2.5-24.x86_64.rpm Chapter 3: Oracle Installation 53 glibc-devel-2.5-24.i386.rpm gcc-4.1.2-42.el5.x86_64.rpm libgomp-4.1.2-42.el5.x86_64.rpm libstdc++-devel-4.1.2-42.el5.x86_64.rpm gcc-c++-4.1.2-42.el5.x86_64.rpm libaio-devel-0.3.106-3.2.x86_64.rpm libaio-devel-0.3.106-3.2.i386.rpm sysstat-7.0.2-1.el5.x86_64.rpm unixODBC-2.2.11-7.1.x86_64.rpm unixODBC-2.2.11-7.1.i386.rpm unixODBC-devel-2.2.11-7.1.x86_64.rpm unixODBC-devel-2.2.11-7.1.i386.rpm The first three packages listed need to be installed together: > rpm -ivh elfutils-libelf-devel-0.125-3.el5.x86_64.rpm elfutils-libelf-devel To install the unixODBC-devel-2 packages, enter the following at the Linux prompt: >rpm –ivh unixODBC-devel-2*rpm Once again, use rpm with the -q option to verify that a package is installed: >rpm –q unixODBC-devel-2.2.11 The installation guide provided by Oracle will have the most up-to-date information for your versions of Oracle and Linux, and point out any dependencies with certain packages and if there are any issues. Kernel Parameters You may need to adjust the kernel parameters if your Oracle system will have high memory needs. Recall from Chapter 2 the example of the error message that appears when the operating system doesn’t have enough memory to mount the /dev/shm file system. Kernel parameters are in the /etc/sysctl.conf file, which can be edited to make the necessary modifications. kernel.shmall = physical RAM size / pagesize kernel.shmmax=½ofphysical RAM, but < 4GB kernel.shmmni =4096 54 Oracle Database Administration for Microsoft SQL Server DBAs kernel.sem = 250 32000 100 128 fs.file-max = 512 x processes fs.aio-max-nr = 1048576 net.ipv4.ip_local_port_range = 9000 65500 net.core.rmem_default = 262144 net.core.mem_max = 4194304 net.core.wmem_default = 262144 net.core_wmem_max = 1048576 After this file is edited, you must activate the changes by running the following at the command prompt as root: sysctl –p Use the following command to view the current settings for a kernel parameter: > /sbin/sysctl -a | grep <param-name> This was a quick overview of the setup for the Linux operating system. The Oracle installation guide will have the details for your specific environment. Storage Requirements Now we need to look at where the database is going to live. There are many storage options available with hardware, configurations, and file systems, and with new hardware developments, even more options may be coming soon. However, we do want to eventually get to actually installing Oracle, so this will not be an all-inclusive discussion about storage, but enough to cover the basics. If you don’t have enough memory in which to store the database— whether it’s SQL Server or Oracle—fast read access is great. For backing up data and applications that are heavy on the transactions, fast writing to the disk is another bonus. In designing the storage layout, striping and mirroring play a definite part. The databases need to be highly available, and the users will always be happier with faster access, so building in fault-tolerant systems Chapter 3: Oracle Installation 55 at the storage level is a necessity. Making it fast is even better. Chapter 10 will cover some I/O tuning and possible issues. Here, we’ll first examine what disk storage is needed, and then look at Oracle Automatic Storage Management (ASM), which can simplify your work by handling much of the storage for you. We’ll also review the types of Oracle files. Disk Storage You will need storage for datafiles and log files, as well as disk space for installing the software, but what other disk storage is required? You will need space for server logs and backups, and possibly a scratch area for exports and working with files. Although you could use certain storage solutions, such as striping, to make your database system work with just two disk drives or one file system, such a setup isn’t ideal. With Linux, it’s possible to just have one mount point and place everything there under different directories. To set up storage for a particular system properly, the DBA needs to understand the different pieces: files, I/O events, and backups. You need to know which are typical events for databases and which are not, and which databases are heavy on read and writes of disk, and how each of these can affect the disk storage needed. Under Windows, you would at least hope for two additional drives besides the C: drive. For example, you might set up disk storage on Windows as follows: ■ D:\oracle Base directory for software and server logs ■ D:\oradata For datafiles and one control file ■ E:\orabackup For backups ■ E:\oraarch For archive logs ■ E:\oraexp For data dump files and exports ■ E:\oradata Another location for control files Control files contain information about the datafiles that can be used for recovery, as discussed in the “Oracle Files” section a little later in the chapter. You should place the control files in different directories and have multiple copies available in case they are needed. 56 Oracle Database Administration for Microsoft SQL Server DBAs Under Linux, you might set up your disk storage as follows (/u0 n is a typical naming convention): ■ /u01/oracle Base directory for software, server logs, and control files ■ /u02/oracle/SID For exports, archives, backups, and control files ■ /u03/oracle/SID For datafiles (numbers can continue to increase) and control files Alternatively, you could use another naming convention such as /ora0 n , and this type of setup: ■ /ora01/oracle Base directory for software ■ /ora01/SID For datafiles and control files ■ /ora02 and subdirectories For export, backups, control files, and so on These are just some examples, intended to demonstrate how you might break up the software, datafiles, and backup files. Storage Management with ASM ASM makes managing datafiles simple. With Oracle Database 11 g R2, ASM can manage all of the files—database files, nonstructured binary files, and external files including text files. This means that all of the discussion in the previous section could actually be ignored. ASM handles managing the disk, adding disk storage, and tuning I/O performance with rebalancing while the storage is up and available to the Oracle databases on that server. The discussion then just comes down to how many disk groups you will create. ASM will take care of mirroring and striping. Different levels of redundancy are available for the disk groups: normal, high, and external. With external, ASM doesn’t provide the redundancy, but it can take advantage of external hardware mirroring. Chapter 3: Oracle Installation 57 With Oracle Database 10 g and even 11 g R2, the ASM installation was part of the database software installation routine. Starting with Oracle Database 11 g R2, ASM is a separate installation using the Grid Infrastructure. Use a different home directory than the database home directory for the installation of ASM, and perform the installation as another user, such as asmadm user. The home directory for ASM contains other pieces, such as Clusterware, which are part of the ASM installation. If you are installing a version of Oracle earlier than 11 g R2, start the installation process of the database software. After you set the home to install the software, an option will come up for choosing which type of install to do, as shown in Figure 3-2. 58 Oracle Database Administration for Microsoft SQL Server DBAs FIGURE 3-2. Choose to install ASM in Oracle Database 11 g R1 or earlier versions After you choose the ASM installation, the Database Configuration Assistant will start to create the instance that is used by ASM. In Figure 3-3, the password is set for the system user, and the parameters to discover the disk groups can be set here as well. Next, create the disk groups. You can also add disk groups later. You should see a list of devices available for the disk groups; if not, the parameter for disk discovery might not be set. Figure 3-4 shows how to set this discovery path, and then select the disks to be part of the disk group. Here is where the redundancy for the disk group is selected. This is just the setup of the ASM instance. In Chapter 10, we will look at how this plays into a highly available database environment. Chapter 3: Oracle Installation 59 FIGURE 3-3. ASM instance creation If you are installing Oracle Database 11 g R2, ASM is a Grid Infrastructure installation. As shown in Figure 3-5, you can install Clusterware and the Grid Infrastructure. With this installation, the creation of the ASM instance, disk groups, and volumes is done by the ASM Configuration Assistant instead of the Database Configuration Assistant. You can also use the ASM command-line utilities ASMCMD and ACFSUTIL to create and manage the disks. Here’s an example of creating a volume group from the operating system command line: ASMCMD > volcreate -d DISKGRPDATA -s 20G volume1 ASMCMD can help manage the instance, with startup and shutdown, disk group, and disk failure management. 60 Oracle Database Administration for Microsoft SQL Server DBAs FIGURE 3-4. ASM disk groups The setup of the ASM disks needs to be done before even installing ASM instance. The disk groups can be created so that they are available for the software install. If using the file manager for the regular files, such as create scripts and parameter files, as well as the datafiles for the database, these disks and storage areas will need to be available for installation. We have just scratched the surface of ASM. It has many more features and options, and is an important piece of a stable database environment. Oracle Files Various types of files are part of the Oracle system. Understanding what these files contain will help you to plan for storage and disk space. Chapter 3: Oracle Installation 61 FIGURE 3-5. ASM installation on Oracle Database 11 g R2 . come up for choosing which type of install to do, as shown in Figure 3-2. 58 Oracle Database Administration for Microsoft SQL Server DBAs FIGURE 3-2. Choose to install ASM in Oracle Database. 4GB kernel.shmmni =4096 54 Oracle Database Administration for Microsoft SQL Server DBAs kernel.sem = 250 32000 100 1 28 fs.file-max = 512 x processes fs.aio-max-nr = 10 485 76 net.ipv4.ip_local_port_range. Database Administration for Microsoft SQL Server DBAs Under Linux, you might set up your disk storage as follows (/u0 n is a typical naming convention): ■ /u01 /oracle Base directory for software, server