红帽全球峰会此内容没有您所选择的语言版本。
7.3. Moving Resources Due to Connectivity Changes
Setting up the cluster to move resources when external connectivity is lost is a two-step process.
- Add a
pingresource to the cluster. Thepingresource uses the system utility of the same name to test if a list of machines (specified by DNS host name or IPv4/IPv6 address) are reachable and uses the results to maintain a node attribute calledpingd. - Configure a location constraint for the resource that will move the resource to a different node when connectivity is lost.
Table 5.1, “Resource Properties” describes the properties you can set for a
ping resource.
| Field | Description |
|---|---|
dampen
| |
multiplier
| |
host_list
|
The following example command creates a
ping resource that verifies connectivity to www.example.com. In practice, you would verify connectivity to your network gateway/router. You configure the ping resource as a clone so that the resource will run on all cluster nodes.
pcs resource create ping ocf:pacemaker:ping dampen=5s multiplier=1000 host_list=www.example.com --clone
# pcs resource create ping ocf:pacemaker:ping dampen=5s multiplier=1000 host_list=www.example.com --clone
The following example configures a location constraint rule for the existing resource named
Webserver. This will cause the Webserver resource to move to a host that is able to ping www.example.com if the host that it is currently running on cannot ping www.example.com
pcs constraint location Webserver rule score=-INFINITY pingd lt 1 or not_defined pingd
# pcs constraint location Webserver rule score=-INFINITY pingd lt 1 or not_defined pingd
'%20d='M201.5%20305.5c-13.8%200-24.9-11.1-24.9-24.6%200-13.8%2011.1-24.9%2024.9-24.9%2013.6%200%2024.6%2011.1%2024.6%2024.9%200%2013.6-11.1%2024.6-24.6%2024.6zM504%20256c0%20137-111%20248-248%20248S8%20393%208%20256%20119%208%20256%208s248%20111%20248%20248zm-132.3-41.2c-9.4%200-17.7%203.9-23.8%2010-22.4-15.5-52.6-25.5-86.1-26.6l17.4-78.3%2055.4%2012.5c0%2013.6%2011.1%2024.6%2024.6%2024.6%2013.8%200%2024.9-11.3%2024.9-24.9s-11.1-24.9-24.9-24.9c-9.7%200-18%205.8-22.1%2013.8l-61.2-13.6c-3-.8-6.1%201.4-6.9%204.4l-19.1%2086.4c-33.2%201.4-63.1%2011.3-85.5%2026.8-6.1-6.4-14.7-10.2-24.1-10.2-34.9%200-46.3%2046.9-14.4%2062.8-1.1%205-1.7%2010.2-1.7%2015.5%200%2052.6%2059.2%2095.2%20132%2095.2%2073.1%200%20132.3-42.6%20132.3-95.2%200-5.3-.6-10.8-1.9-15.8%2031.3-16%2019.8-62.5-14.9-62.5zM302.8%20331c-18.2%2018.2-76.1%2017.9-93.6%200-2.2-2.2-6.1-2.2-8.3%200-2.5%202.5-2.5%206.4%200%208.6%2022.8%2022.8%2087.3%2022.8%20110.2%200%202.5-2.2%202.5-6.1%200-8.6-2.2-2.2-6.1-2.2-8.3%200zm7.7-75c-13.6%200-24.6%2011.1-24.6%2024.9%200%2013.6%2011.1%2024.6%2024.6%2024.6%2013.8%200%2024.9-11.1%2024.9-24.6%200-13.8-11-24.9-24.9-24.9z'/%3e%3c/svg%3e){kind=small}