What is HostChecker?

The HostChecker is a standalone program which validates that host machines are configured correctly before the Delphix Engine uses them as data sources and provision targets.

Please note that HostChecker does not communicate changes made to hosts back to the Delphix Engine. If you reconfigure a host, you must refresh the host in the Delphix Engine in order for it to detect your changes.

You can run the tests contained in the HostChecker individually, or all at once. You must run these tests on both the source and target hosts to verify their configurations. As the tests run, you will either see validation messages that the test has completed successfully, or error messages directing you to make changes to the host configuration.

Prerequisites

Procedure

  1. Download the HostChecker tarball matching the host's operating system from https://download.delphix.com/ (for example: hostchecker_linux_x86.tar).

  2. Create a working directory and extract the HostChecker files from the HostChecker tarball.

    mkdir dlpx-host-checker
    cd dlpx-host-checker/
    tar -xf hostchecker_linux_x86.tar
  3. Change to the working directory and enter this command. Note that for the target environments, you would change source to target.

    $ cd hostchecker
    $ ./hostchecker.sh 
    Extracting the JDK from the tarball jdk.tar.gz.
    Please enter whether this machine is a source or a target:target
    1: Check ASE environment
    2: Check all ASE instances
    3: Check all the Oracle installations
    4: Check homedir permissions
    5: Check Linux Performance Settings
    6: Check mkdir and rmdir
    7: Check the MySQL installation
    8: Check network port access
    9: Check the Oracle CRS home
    10: Check for ssh connectivity
    11: Check sshd_config for timeout configuration
    12: Check user sudo privileges
    13: Check toolkit path
    all: Execute all checks
    quit: Exits
    Please select an option:

    Don't Run as Root

    Don't run the HostChecker as root; this will cause misleading or incorrect results from many of the checks.

  4. Select which checks you want to run. We recommend you run all checks (excluding Oracle and MySQL) if you are running Hostchecker for the first time.

  5. Pass in the arguments the checks ask for.
  6. Read the output of the check. 

  7. The error or warning messages will explain any possible problems and how to address them. Resolve the issues that the HostChecker describes. Don't be surprised or undo your work if more errors appear the next time you run HostChecker, because the error you just fixed may have been masking other problems.
  8. Repeat steps 3–7 until all the checks return no errors or warnings.

Tests Run

Test

SAP ASE Source

SAP ASE Target

Description
Check SAP ASE environmentXX
  • Checks that the $SYBASE environment variable exists for interactive logs. NOTE: It is still necessary to check that it is defined for non-interactive logins (ssh user@host env | grep SYBASE).
  • Checks that the "isql_r64" binary can be found underneath the $SYBASE environment variable.
Check All SAP ASE instancesXX

Attempts to connect to each running SAP ASE instance via "isql_r64" (utilizing the $SYBASE/interfaces file) and execute the following queries:

select @@servername
select count(*) from master..syslisteners
select count(*) from master..sysservers
select count(*) from master..sysdatabases
select count(*) from master..sysusages
select @@version
select @@maxpagesize
SELECT srvnetname FROM master..sysservers WHERE srvname='SYB_BACKUP'

Check all the Oracle installationsN/AN/A
Check homedir permissionsXX

Check that the home directory, the ~/.ssh directory, and the ~/.ssh/authorized_keys file exist, that they are owned by the user invoking this check, and that they are not 'group' or 'other' writable.

Check <OS> Performance Settings
XCheck target's kernel settings necessary to optimize performance. 
Check mkdir and rmdir
XTests that the user can mkdir and rmdir under both the toolkit directory and the specified mount path.
Check the MySQL installationN/AN/A
Check network port accessXXCan be used to test access to specified ports on the Delphix Engine. See Network and Connectivity Requirements for SAP ASE Environments for a list of ports.
Check the Oracle CRS homeN/AN/A
Check Oracle DB InstanceN/AN/A
Check for ssh connectivity
XXVerifies that the environment is accessible via SSH
Check sshd_config for timeout configuration
XCheck that sshd_config does not contain ClientAliveInterval or ClientAliveCountMax entries.
Check toolkit PathXXVerifies that the toolkit installation location has the proper ownership, proper permissions, and enough free space.
Check user sudo privileges
XXVerifies that the operating system user can execute certain commands with necessary privileges via sudo. This only needs to be run on target environments. See the topic Requirements for SAP ASE Environments and Databases for more information.

Related Topics