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diff --git a/doc/dev/cephadm/compliance-check.rst b/doc/dev/cephadm/compliance-check.rst new file mode 100644 index 000000000..eea462445 --- /dev/null +++ b/doc/dev/cephadm/compliance-check.rst @@ -0,0 +1,121 @@ +================ +Compliance Check +================ + +The stability and reliability of a Ceph cluster is dependent not just upon the Ceph daemons, but +also the OS and hardware that Ceph is installed on. This document is intended to promote a design +discussion for providing a "compliance" feature within mgr/cephadm, which would be responsible for +identifying common platform-related issues that could impact Ceph stability and operation. + +The ultimate goal of these checks is to identify issues early and raise a healthcheck WARN +event, to alert the Administrator to the issue. + +Prerequisites +============= +In order to effectively analyse the hosts that Ceph is deployed to, this feature requires a cache +of host-related metadata. The metadata is already available from cephadm's HostFacts class and the +``gather-facts`` cephadm command. For the purposes of this document, we will assume that this +data is available within the mgr/cephadm "cache" structure. + +Some checks will require that the host status is also populated e.g. ONLINE, OFFLINE, MAINTENANCE + +Administrator Interaction +========================= +Not all users will require this feature, and must be able to 'opt out'. For this reason, +mgr/cephadm must provide controls, such as the following; + +.. code-block:: + + ceph cephadm compliance enable | disable | status [--format json] + ceph cephadm compliance ls [--format json] + ceph cephadm compliance enable-check <name> + ceph cephadm compliance disable-check <name> + ceph cephadm compliance set-check-interval <int> + ceph cephadm compliance get-check-interval + +The status option would show the enabled/disabled state of the feature, along with the +check-interval. + +The ``ls`` subcommand would show all checks in the following format; + +``check-name status description`` + +Proposed Integration +==================== +The compliance checks are not required to run all the time, but instead should run at discrete +intervals. The interval would be configurable under via the :code:`set-check-interval` +subcommand (default would be every 12 hours) + + +mgr/cephadm currently executes an event driven (time based) serve loop to act on deploy/remove and +reconcile activity. In order to execute the compliance checks, the compliance check code would be +called from this main serve loop - when the :code:`set-check-interval` is met. + + +Proposed Checks +=============== +All checks would push any errors to a list, so multiple issues can be escalated to the Admin at +the same time. The list below provides a description of each check, with the text following the +name indicating a shortname version *(the shortname is the reference for command Interaction +when enabling or disabling a check)* + + +OS Consistency (OS) +___________________ +* all hosts must use same vendor +* all hosts must be on the same major release (this check would only be applicable to distributions that + offer a long-term-support strategy (RHEL, CentOS, SLES, Ubuntu etc) + + +*src: gather-facts output* + +Linux Kernel Security Mode (LSM) +________________________________ +* All hosts should have a consistent SELINUX/AppArmor configuration + +*src: gather-facts output* + +Services Check (SERVICES) +_________________________ +Hosts that are in an ONLINE state should adhere to the following; + +* all daemons (systemd units) should be enabled +* all daemons should be running (not dead) + +*src: list_daemons output* + +Support Status (SUPPORT) +________________________ +If support status has been detected, it should be consistent across all hosts. At this point +support status is available only for Red Hat machines. + +*src: gather-facts output* + +Network : MTU (MTU) +________________________________ +All network interfaces on the same Ceph network (public/cluster) should have the same MTU + +*src: gather-facts output* + +Network : LinkSpeed (LINKSPEED) +____________________________________________ +All network interfaces on the same Ceph network (public/cluster) should have the same Linkspeed + +*src: gather-facts output* + +Network : Consistency (INTERFACE) +______________________________________________ +All hosts with OSDs should have consistent network configuration - eg. if some hosts do +not separate cluster/public traffic but others do, that is an anomaly that would generate a +compliance check warning. + +*src: gather-facts output* + +Notification Strategy +===================== +If any of the checks fail, mgr/cephadm would raise a WARN level alert + +Futures +======= +The checks highlighted here serve only as a starting point, and we should expect to expand +on the checks over time. |