There are different kind of memory measurement metrics in Linux. These are the differences: Code Name Description vsz virtual memory...
Hint You're not able to control which redis replica will chosen for the failover. Connect to your sentinel instance...
If one etcd node is no longer a member of the remaining etcd cluster or fails to connect you need...
It is possible to add custom http header to request made by the docker CLI client. This can be used...
journalctl _CMDLINE=dockerd podman journalctl SYSLOG_IDENTIFIER=podman identifying potential filter fields journalctl -o verbose journalctl -o json | jq
...either build a ES cluster or you disable the replicas. Building a cluster is beyond the scope of this card, but we can have a look how we can disable...
...localhost:9200/_cat/shards?pretty' | grep UNASSIGNED If it's a replica (r in the column befor the UNASSIGNED) and you are on a single node elasticsearch you need to disable replicas...
Investigate why mails are frozen The exim documentation says: Freezing occurs when a bounce message encounters a permanent failure because...
With Ubuntu 24.04 it's not longer possible to setup FDE with BTRFS The new installer won't offer you...
You can use proxy_hide_header in different contexts: Syntax: proxy_hide_header field; Default: — Context: http, server, location
To connect to the serial console of an EC2 instance, you can use the aws cli. Add your public ssh...
Maintain this feature branch on a regular basis to not get too far behind production. Setup a reminder to either merge the branch or drop it. Inform the colleagues...
Wondering what these numbers in the mount entries in /etc/fstab are meaning? The first number fs_freq When this field...
We often do some HTTP requests to fetch the data we want to check for certain criteria. Testing this in...
...systemd service unit: # Run `openssl speed` as unit run-benchmark.service $ sudo systemd-run --unit=run-benchmark openssl speed # Query the current status $ systemctl status run-benchmark.service ● run-benchmark.service - /usr/bin/openssl speed Loaded: loaded (/run/systemd/transient/run-benchmark.service...
...CGroup: /system.slice/run-benchmark.service └─18344 /usr/bin/openssl speed # Get the logs $ sudo journalctl -u run-benchmark.service -- Logs begin at Mon 2022-03-07 13:45:18 CET, end at Wed...
When you are using the default MIME-Type configuration and your application allows uploading files, it can be a security...
A convenient way to test SNS Subscription Filter Policies is using an email address as the subscription endpoint. However, for...
In our monitoring, RabbitMQ queues like aliveness-test may show up as unresponsive, with a ping timeout after 10 seconds...
It's not possible to change the bwlimit of Proxmox storages via the Web-UI (at least in Proxmox 7...
When receiving a new SSL-Certificate for an existing SSL-key it should be checked that they match cryptographically.
It is a good idea to use named variables for storing parameters of a script or function. We can use...
To see all jails: fail2ban status Our $JAIL is usually ssh. To see which IPs are banned currently: fail2ban-client...
If you have a very large datadir in MariaDB and you want to transfer the data to another host (e.g...
Ever felt annoyed by AWS Free Tier limit alert emails? Just disable them: Billing preferences -> Cost Management Preferences -> Receive Free...
...an attack) will fill up our conntrack tables. Decide which option resolves the situation best with minimal impact on production: $ sudo conntrack -D -s 49.12.3.247 # example: delete all conntrack table...