Posts By: jonny

LHT65 setup and UART Serial Connection

I wired a CP2102 USB to TTL Serial Converter to the LHT65 UART connector – see images below: Then on the linux command line ran: dmesg | tail to check the device name that was added by the system. I then connected to that serial device using screen: sudo screen /dev/ttyUSB0 If you type you… Read more »

Proxmox: adding internal private nework

In this scenario I wanted to be able to run several VMs that can communicate with each other on a private subnet e.g. 10.10.10.* and also be access the internet for updates etc. Eventually I want to expose some of the internal services. My proxmox server has one network interface with an internet facing IP… Read more »

SELinux: Create Policy for NRPE Writing

Had a problem with Nagios/NRPE checks that are configured to write a status file as part of their check. The path /var/logstate was the target created the policy below. Andrew (Urban Penguin) Youtube video is an excellent resource. Install selinux utilities: yum install policycoreutils policycoreutils-devel setools-console setroubleshoot The audit log (/var/log/audit/audit.log) was showing the type=AVC… Read more »

Nagios NRPE omreport errors

Nagios check for Dell OpenManage was failing after upgrade to srvadmin 9.2 with: UNKNOWN: Problem running ‘omreport chassis memory’: Error: SMStatus: 700 UNKNOWN: Problem running ‘omreport chassis batteries’: Error! XML Transformation failed UNKNOWN: Problem running ‘omreport chassis pwrmonitoring’: Error: SMStatus: 700 UNKNOWN: Problem running ‘omreport chassis removableflashmedia’: Error: SMStatus: The check command: /usr/lib64/nagios/plugins/check_openmanage -s -b… Read more »

check_mk: Check http service

In the WATO menu choose ‘Check Plugins’ and then ‘Networking checks without an agent’. Find the ‘HTTP/HTTPS connection’ option and then click on ‘Check HTTP service’ beside Parameter rule set: Scroll down to the bottom and click ‘Create rule in folder’ Set the parameters for the check , then save and activate.

check_mk: Check APT updates

On your check_mk install under the WATO menu navigate to ‘Monitoring Agents’ find and click on the link for ‘Check for APT updates (Debian, Ubuntu)’. This is the check plugin to add to the server so copy that code. Copy the contents of that check file to a file named mk_apt file in the /usr/lib/check_mk_agent/local… Read more »

ThingsBoard API: Get telemetry values

I’m using Insomnia for testing and after already getting the auth token I use that in Insomnia as follows: The URL I used for the query was: The word device in there does not need to be changed by the ID field that follows it should be changed to the UUID of your device. You… Read more »

Blink Hard Disk Light on Dell

To blink the light on a hard disk on Dell Server from the command line first get a list of the physical disks so you can check the disk ID: omreport storage pdisk controller=0 then to blink the disk: omconfig storage pdisk action=blink controller=0 pdisk=0:0:2