Chris Paquin

AI, Virtualization, Containers, Infrastructure, Linux

Tag: disable

  • RHEL6 – Display and Modify SELinux Modes

    There are three basic commands that you can use to display and modify SELinux modes. They are as follows

    • getenforce

    • setenforce

    • sestatus

    The first two are installed as part of the package, libselinux-utils. The sestatus is installed as part of policycoreutils.

    Setenforce will enable or disable SELinux temporarily. Use 0 to disable and 1 to enable as shown below.

    #setenforce 0
    #setenforce 1

    If you need need your change to be persistent across reboots edit /etc/selinux/config.

    # This file controls the state of SELinux on the system.
    # SELINUX= can take one of these three values:
    #       enforcing - SELinux security policy is enforced.
    #       permissive - SELinux prints warnings instead of enforcing.
    #       disabled - SELinux is fully disabled.
    SELINUX=enforcing
    # SELINUXTYPE= type of policy in use. Possible values are:
    #       targeted - Only targeted network daemons are protected.
    #       strict - Full SELinux protection.
    SELINUXTYPE=targeted

    Getenforce is used to query your SELinux Status as seen below

    [root@vpaquin01 selinux]# getenforce 
    Enforcing

    Sestatus give you the same information as getenforce but in a bit more detail

    [root@vpaquin01 selinux]# /usr/sbin/sestatus
    SELinux status:                 enabled
    SELinuxfs mount:                /selinux
    Current mode:                   enforcing
    Mode from config file:          enforcing
    Policy version:                 24
    Policy from config file:        targeted


  • How to Disable DRS for one VM in a DRS Enabled Cluster

    How to Disable DRS for one VM in a DRS Enabled Cluster

    VMware DRS (Distributed Resource Scheduler) is a feature of ESX that balances
    computing workloads with available resources in a virtualized
    environment. 

    When you enable a cluster for DRS, VirtualCenter continuously monitors the distribution
    of CPU and memory resources for all hosts and virtual machines in the cluster. DRS compares these metrics to what resource utilization ideally should be given the attributes of the resource pools and
    virtual machines in the cluster, and the current load.

    Note that DRS is only available in ESX Enterprise or above.

    When DRS is enabled in a cluster, ESX then will automagically vmotion guest VMs to other hosts in your cluster in an attempt to ballance out the load evenly across the cluster. However, sometimes this behavior is not always desired. For exmaple if you have a large VM that you want to stay pinned to a particular host.

    In order to override the default DRS cluster settings for a vm, you need to do the following.

    1. Right Click on your cluster and then click on “edit settings“
    2. Under DRS, click on “Virtual Machine Options“
    3. Locate the particular VM and the drop down box under “Automation Level“
    4. Change “Default (Fully Automated)” to “Manual“