Flush DNS cache in Ubuntu 20.xx and above
On bash, run – sudo systemd-resolve --flush-caches Should be done. KjKj [/.] Sreekumar programs computers as a hobby and profession. Into programming from...
Category: Technology
Change the datacenter set in cassandra-rackdc on Ubuntu
Problem: Changing just the datacenter name in cassandra-rackdc.properties gives the error: Cannot start node if snitch's data center [newName] differs from prev...
RabbitMQ installation fails in in the last leg of setting up in ubuntu 20.04
Error: Reason: libtinfo.so library missing. Solution: Note: No need to reattempt the installation. KjKj [/.] Sreekumar programs computers as a hobby and profess...
Fix : Docker node down after restart
Problem: One of the docker nodes does not start up after restart. Error in the log is msg="error removing task " error="incompatible value" Reason: Docker swarm...
IP Telephony – bit rates of audio formats, and other notes
The bit rates for the most common audio formats – ALAW 8 BITS ULAW 8 BITS PCM 16 BITS SIGNED/UNSIGNED ADPCM 8 BITS The endian-ness for more than one byte ...
Fix: Cannot start container Subnet sandbox join failed error from docker
Error : Few docker containers don’t start up. In the /var/log/syslog they give the error “Cannot start container Subnet sandbox join failed…&#...
React Ajax call on load gives : “Error: Should not already be working.”
Problem : On page refreshes, the ajax calls in the componentDidMount functions throws the error : “Error: Should not already be working.” Reason : P...
Fix : The repository ‘http://archive.ubuntu.com/ubuntu disco-backports Release’ no longer has a Release file.
Issue : When doing an apt update, we get the this error.The repository ‘http://archive.ubuntu.com/ubuntu disco-backports Release’ no longer has a Re...
Cannot connect to DB from a process inside Docker container ? This could fix it.
I had recently hit a blocker to production deployment, when my processes just won’t connect to my Cassandra DB from within their containers. This is how I...
Open ports in Ubuntu’s firewall using IP Tables
On the terminal, do the following to open port 80 sudo iptables -A INPUT -p tcp --dport 80 -j ACCEPT sudo iptables -F Persisting the rule changes across boot cy...