There was a alert showing that the swap free space is low in a RHEL 5.6 box. I logged in and checked, the box has 13G RAM, but only 1G swap. First, this is not a good practice, as RedHat recommends 4G swap for RHEL5 with 4-16G RAM. free -m total used free shared buffers … Continue reading Clear Linux memory cache
Configure Synergy as systemd service
Synergy is a mouse and keyboard sharing software (not free anymore). I use it for sharing my Fedora 20 K&M with my Windows box. As Fedora 20 replaces init with systemd, there is no rc.local where I can add my own startup script. Systemd provides a easy way to allow you create your own system service. … Continue reading Configure Synergy as systemd service
Puppet push Nagios
With the storeconfigs enabled, I am able to push Naigos via Puppet. It is really simple and straighforward, as Puppet already support nagios_* type. How it works? Below is my sample codes. It can be downloaded from here. sys_nagios::client is the class for Nagios client, it sends the hosts' facts to Puppet master then the data … Continue reading Puppet push Nagios
Incomplete certificate chain
There are 3 methods to test the incomplete certificate chain: 1) https://www.ssllabs.com/ssltest/analyze.html?d=example.com The error is: Chain issues Incomplete 2) curl -v -o /dev/null https://example.com The error is: * NSS error -8179 (SEC_ERROR_UNKNOWN_ISSUER) * Peer's Certificate issuer is not recognized. 3) openssl s_client -showcerts -verify 10 -connect example.com:443 The error is: Verify return code: 21 (unable … Continue reading Incomplete certificate chain
Puppet – Configuring Storeconfigs for MySQL
Exported resource allow node to share information with each other. This is useful when one node has information that another node needs in order to manage a resource. The common cases are monitoring and backups. To use exported resource in Puppet, the storeconfigs has to be enabled. This will allow puppet to save data (resources, … Continue reading Puppet – Configuring Storeconfigs for MySQL
