As we can see from above, we are getting random blank spaces in the graph. Possible causes for this are
Using SNMPv1 doesn’t support more then 125Mbps.
https://community.librenms.org/t/librenms-gaps-in-graphs/5209/2
Could be the server is not able to consistently complete polling of devices.
https://community.librenms.org/t/gaps-in-data-gaphs/469/2
Prerequisites
In this example, the server is already using Let’s Encrypt to create the certificate for a LibreNMS server. So all we are doing is copying the certificate to a Grafana directory, putting the correct permissions on it, and updating the Grafana config file to use the certificate.
Steps
In the following commands, change librenms.incredigeek.com to the directory that Let’s Encrypt is using for your fully qualified domain name (FQDN). Usually it is just your FQDN, but could also have -0001 or something appended to the end.
cp -f /etc/letsencrypt/live/librenms.incredigeek.com/privkey.pem /etc/grafana/ cp -f /etc/letsencrypt/live/librenms.incredigeek.com/fullchain.pem /etc/grafana/ chown root:grafana /etc/grafana/*.pem chmod 640 /etc/grafana/*.pem Enable grafana on system bootup
In the above, we are copying the privkey.pem and fullchain.pem to /etc/grafana. We are then setting the correct owner/permissions on the files so that the Grafana service can read the certificate.
This is super easy. Open up the Grafana config file in /etc/grafana.ini
vi /etc/grafana.ini
Find the following variables and configure them like so
protocol = https
cert_file = /etc/grafana/fullchain.pem
cert_key = /etc/grafana/privkey.pem
Restart Grafana
systemctl restart grafana-server.service
You should now have a working SSL certificate for the site.
Let’s Encrypt certificates need to be updated frequently. This means that we should automate the above steps to avoid any down time. After all, a monitoring tool with down time defeats the purpose of monitoring.
We’ll need to create a root crontab
sudo crontab -e
Add the following changing out the FQDN to your FQDN.
0 0 1 * * cp -f /etc/letsencrypt/live/librenms.incredigeek.com/privkey.pem /etc/grafana/ && cp -f /etc/letsencrypt/live/librenms.incredigeek.com/fullchain.pem /etc/grafana/ && chown root:grafana /etc/grafana/*.pem && chmod 640 /etc/grafana/*.pem
This is set to run once a month. Change if desired. Also change out librenms.incredigeek.com with your FQDN.
Note about domain name and IP addresses. Let’s Encrypt will not create a certificate for an IP address. You should be using a domain name instead (i.e. networkmonitoring.yourdomain.com) If the certificate is installed, and you access it via the IP address, you will receive a HTTPS error in your browser.
Renaming of 192.168.1.20 failed . Does your web server have permission to modify the rrd files?
First thing to check is verify that the IP address is not already being monitored.
If you are getting the above error while trying to rename a device in LibreNMS, you may need to rerun some of the SELinux commands from the installation.
SSH into the server and run
restorecon -RFvv /opt/librenms
Now try renaming the device. Note that you can’t rename the device if the name/ip to a name that is being used by a different device.
If you continue to have issues, check the permissions from the installation guide (Official guide here)
You can also check for SELinux errors with
audit2why < /var/log/audit/audit.log
More SELinux info here
There are some differences on setting up RRDReST on CentOS 8, Almalinux 9 vs CentOS 7
If you are setting this up to use with LibreNMS and Grafana, check out the rest of the this article. https://www.incredigeek.com/home/setting-up-grafana-on-librenms/
All the docker commands have been swapped out for podman.
Podman is default on CentOS 8 and later and is for the most part a drop in replacement for Docker.
sudo yum install -y podman podman-compose sudo systemctl enable podman
Create docker compose file with the following options
vi podman-compose.yml
Change the TZ to your time zone. If you have issues with the graphs, most likely something is off with the time zone between this container and Grafana/LibreNMS server
version: "3.5"
services:
rrdrest:
image: michaelwadman/rrdrest:latest
container_name: rrdrest
restart: always
volumes:
- "/opt/librenms/rrd:/opt/librenms/rrd:Z"
environment:
- TZ=America/Denver
Note that the :Z is needed for SELinux to allow RRDReST to access the sub folders. AKA. the rrd files.
Save the file and start and setup the container with
sudo podman-compose up -d
You will need your docker container IP address to setup the connection in Grafana
sudo docker exec -it rrdrest ip addr | grep eth0
The “restart: always” option does not appear to work on systems with podman. We can create a systemd service instead.
Use the following command to automatically create a
podman generate systemd rrdrest
Copy the contents to a new file in
/etc/systemd/system/rrdrest.service
Enable the new service with
systemctl enable rrdrest
Congratulations. RRDReST is now setup and running.
In the post, we’ll be adding a custom OID for a Ubiquiti Solar Charge Controller.
Check out the following post if you are trying to add a Ubiquiti Solar Charge controller graph to LibreNMS. Otherwise you may need to do some googling around looking for the OID.
Go to your device -> Settings(Little Gear) -> Custom OID -> +Add New OID
Couple notes about the information.
– There needs to be a 0 after the end of the OID.
– Data Type needs to be Gauge, Not Counter. A gauge can go up and down. A counter just counts up.
Hit “Test OID” and you should get a little notification saying it got a value for the OID. In this case 25572.
Now Hit “Save OID”
Now LibreNMS should start graphing our Custom OID. You may need to give it a minute to start showing data.
The graphs show up under Graphs -> Custom OID
Thanks to the guys who put together the information at the following links.
https://wadman.co.nz/2021/01/02/Viewing-LibreNMS-data-in-Grafana/
https://www.reddit.com/r/LibreNMS/comments/ojc8cc/how_to_almost_natively_integrate_librenms_and/
I ran into some issues trying to get this to work. So here are some of my notes. I already had a LibreNMS installation set up.
NOTE FOR CENTOS 8, ALMALINUX 8 and 9
The steps for installing RRDReST are slightly different. Check out the following post.
https://www.incredigeek.com/home/setting-up-rrdrest-on-centos-8-or-almalinux-9/
I had issues installing RRDReST. I am guessing it had to do with it accessing files. I was able to install it in a docker container.
sudo yum install -y docker docker-compose
sudo systemctl enable docker
Create docker compose file with the following options
vi docker-compose.yml
Change the TZ to your time zone. If you have issues with the graphs, most likely something is off with the time zone between this container and Grafana/LibreNMS server
version: "3.5"
services:
rrdrest:
image: michaelwadman/rrdrest:latest
container_name: rrdrest
restart: always
volumes:
- "/opt/librenms:/opt/librenms"
environment:
- TZ=America/Denver
Save the file and start and setup the container with
sudo docker-compose up -d
You will need your docker container IP address to setup the connection in Grafana
sudo docker exec -it rrdrest ip addr | grep eth0
Congratulations. You should now have a RRDReST docker container that will auto start on system boot and has the correct time zone.
Basic steps are as follows
There is not anything special with installing Grafana on the same server as LibreNMS. You can follow the official guide to install it
https://grafana.com/docs/grafana/latest/installation/
After Grafana is installed, install the JSON API data source. You can do this using the grafana-cli
grafana-cli plugins install marcusolsson-json-datasource
A note on SSL/TLS certificates. If you have an SSL certificate for LibreNMS, you can use it for grafana. If you run into issues, try copying the cert (fullchain.pem, privkey.pem) to /etc/grafana/
You’ll most likely need to change owner
sudo chown root:grafana /etc/grafana/*.pem
And maybe the file permissions.
sudo chmod 640 /etc/grafana/*.pem
This is fairly straight forward.
grafana-cli plugins install marcusolsson-json-datasource
In Grafana, go to Configuration -> Data Sources -> Add data source
In Grafana, go to Configuration -> Data Sources -> Add data source
You should now be able to view your dashboard and use the drop down menus to select devices
There were a couple of issues I ran into while trying to get everything working together.
Issue: When trying to run RRDReST with uvicorn, I was never able to access the rrd files, even the test rrd files that are included when installing RRDReST. I am guessing it is either a permisions issue, or something unable to access the files.
Work around: Install RRDReST via Docker container.
Issue: Get a “JSON API: Bad Request” when trying to set up the LibreNMS API Data Source in Grafana.
Work around: Install a valid SSL Certificate and set up a DNS record so you can access LibreNMS at librenms.yourdomain.com.
More info: I would assume that “Skip TLS Verify” would work with or without a valid certificate, but it would not work for me. There are potentially some other options with modifying how Nginx or Apache is set up that would get this working. If you setup Grafana to use a SSL certificate, you may need to copy the certificate files (fullchain.pem, privkey.pem) to /etc/grafana/ and run “chown root:grafana *.pem” to let grafana have access to the files.
Running the ./validate.php script returns the following error
[FAIL] Python3 module issue found: 'Required packages: ['PyMySQL!=1.0.0', 'python-dotenv', 'redis>=3.0', 'setuptools', 'psutil>=5.6.0', 'command_runner>=1.3.0']
Package not found: The 'command_runner>=1.3.0' distribution was not found and is required by the application
'
[FIX]:
pip3 install -r /opt/librenms/requirements.txt
Running the [FIX] throws an error saying gcc failed with exit status 1.
Fortunately this issue is easy to resolve.
First we need to install python3-devel
sudo yum install python3-devel
Next, as the librenms user, run the pip command to install the requirements.
pip3 install --user -U -r /opt/librenms/requirements.txt
Run ./validate.php to verify that everything is working.
Recently I started getting the following error while running ./validate.php.
$ sudo -u librenms ./validate.php
====================================
Component | Version
--------- | -------
LibreNMS | 21.8.0-41-g0a76ca4
DB Schema | 2021_08_26_093522_config_value_to_medium_text (217)
PHP | 7.4.20
Python | 3.6.8
MySQL | 10.5.10-MariaDB
RRDTool | 1.4.8
SNMP | NET-SNMP 5.7.2
====================================
[OK] Composer Version: 2.1.6
[OK] Dependencies up-to-date.
[OK] Database connection successful
[FAIL] Database: incorrect column (notifications/datetime)
[FAIL] Database: incorrect column (users/created_at)
[FAIL] We have detected that your database schema may be wrong, please report the following to us on Discord (https://t.libren.ms/discord) or the community site (https://t.libren.ms/5gscd):
[FIX]:
Run the following SQL statements to fix.
SQL Statements:
SET TIME_ZONE='+00:00';
ALTER TABLE `notifications` CHANGE `datetime` `datetime` timestamp NOT NULL DEFAULT '1970-01-02 00:00:00' ;
ALTER TABLE `users` CHANGE `created_at` `created_at` timestamp NOT NULL DEFAULT '1970-01-02 00:00:01' ;Reading online it sounds like some of the recent changes are causing the issue. Looks fairly easy to resolve though.
First we’ll need to get a MySQL prompt. We’ll do that by running
mysql -u librenms -p librenms
It’ll ask use for the librenms user’s mysql password.
Once we have the MySQL prompt we can just copy and paste the commands in.
SET TIME_ZONE='+00:00'; ALTER TABLE `notifications` CHANGE `datetime` `datetime` timestamp NOT NULL DEFAULT '1970-01-02 00:00:00' ; ALTER TABLE `users` CHANGE `created_at` `created_at` timestamp NOT NULL DEFAULT '1970-01-02 00:00:01' ;
Type ‘quit’ to exit MySQL and lets run the validate script again.
sudo -u librenms ./validate.php
Everything should check out OK.
The above error can be resolved by dropping the port_groups table in mysql. You may double check that there is no information in the table. I checked this instance and it didn’t have any data in the table so I dropped it with
drop table port_groups;
I then ran the lnms command again and it created the table and started migrating.
Some quick notes on manually moving LibreNMS to a new server. For more detailed instructions you can refer to the following post
Recovering LibreNMS from crashed XenServer VM
Steps
Backing up LibreNMS files
LibreNMS stores all it’s files in /opt/librenms
Quick and easy way to back up the LibreNMS files is to use tar.
tar zcvf librenms_backup.tgz /opt/librenms
Migrating Database
I believe you can copy the whole /var/lib/mysql directory. Should be able to use the above command. If not you can do a mysqldump and then import it on the new system.