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Alter Column Type for Mysql without downtime

We did this by using pt-online-schema-change 1. Since we are using RDS with Read Replica, and the tool require log_bin_trust_function_creators = 1, we did a failover to Read Replica, modifying parameter group of Master, reboot Master, then failback to Master and repeat this for Read Replica. If you have SUPER privilege of the DB, skip this step. 2. Prepare a…

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Laravel in Docker on the Cloud – Part 1

I has been asked how to make Laravel run in Docker, and more importantly how to deploy it to a production server, since then I have been exploring for options and Laradocks seems to be a simplified way to go for. So before digging into Laradock, will be doing a vanilla dockerization to get the concept clear first. 1.  Get…

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Alibaba Cloud, Pick the right instance type

When we first tried to launch our first instance on Alibaba Cloud, intuitively we picked the default burstable type T5. Once launched, we are shocked, by the speed of running a simple apt-get update, how can it be so slow, it took 2 minutes for it to be completed. Kept exploring and found this instance type: The cost is slightly…

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Letsencrypt failed to renew

We were getting this letsencrypt renewal error on some Ubuntu 16.04 machines: OSError: Command /opt/eff.org/certbot/venv/bin/python2.7 – setuptools pkg_resources pip wheel failed with error code 1 Googling around, hit a few walls and finally found the solution, just need to run this in Ubuntu: export LC_ALL=”en_US.UTF-8″ export LC_CTYPE=”en_US.UTF-8″ Then continue on with the letsencrypt-auto script will do.

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Ubuntu run out of space?

If you are getting ‘running out of space’ from your SSH console, but running a df -h shows that there are still plenty of free space left, then most likely inode is the one that run out. To confirm it, just run the command df -i from the result you should be able to a 100% in the mount point, for…

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Cloud – From Freedom to Jail, then back to Freedom

Freedom and flexibility are the main reasons people move to cloud, especially when there are tools like AWS RDBMS. They allow you to move to cloud and freed from your current on-premise vendor. With a BONUS! They also provide the tool that can help you to convert your database from one platform to another, FREEDOM!!! But without realizing it, we are merely…

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Cloud – Who stolen my vCPU ?

As discussed in previous posts like public vs private cloud, you are getting vCPU for your public cloud servers, which is shared among other VMs in the same hypervisor. But how do you know if the hypervisor,  the physical hardware CPU itself is being overpopulated? What you need to do is: SSH to your server Run the top command: type top…

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Public cloud and Private cloud

What’s the difference between Public and Private The only main difference between the two is simple: Using public cloud: Sharing the physical hardware with other user Using private cloud: All the VM is sitting on your dedicated servers, sharing resource with no others but your own VM A wider definition of ‘Cloud’ itself could simply be – Offsite infrastructure /…

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