The importance of running a validator in blockchain networks since their inception

Chainode Capital, as one of the P-REP candidates for the 22 open positions has successfully run a validator, Chainode_Capital_1, on ICON Testnet since phase 1.

With phase 2 we elevated our game and we started a second validator, Chainode_Capital_2, as it can be seen in the screenshot below.

There were many reasons behind this decision, as running a second validator also implies doubling the costs and we wouldn’t have done it just for fun or visibility.

Our main reasons for running a second validator on Testnet phase 2 are the following:

• Support the ICON Testnet Network by running a stable validator, Chainode_Capital_1, without directly influencing its performance or uptime;
• Run a second validator, Chainode_Capital_2, for designing and implementing a redundant and secure validator architecture;
• Improve the security of the whole ICON Network by running through some scenarios like having a backup validator ready to jump in, using alerts in case our instance is down or using a bastion host to access the validator;
• Design and implement a fail-over strategy in case of validator failure, resynchronisation of the validator, use of blockchain backups and checkpoints;
• Tests of different implementations and configurations;
• Tests of different cloud providers like Vultr and AWS.

Therefore, we had our validators, Chainode_Capital_1 running on Vultr in Amsterdam — The Netherlands since the beginning of phase 1 and Chainode_Capital_2 running on AWS in Frankfurt — Germany starting with the phase 2 of Testnet.

In addition, we used a bastion host positioned in a public area in order to access the two block producers, so SSH connections were only accepted from the bastion host.

For us it was also very important to implement an alerting mechanism in order to be notified and informed when our validator is down. Thus, we implemented and tested an alerting mechanism.

Our strategy for Mainnet is to have an active validator and once it is down, we will swap it with a backup placed in a different availability zone, and maybe also on another cloud provider. The backup validator will be ready to jump in and continue the work of the active validator.

Another topic worth mentioning is the importance of having a blockchain checkpoint and understanding what it actually means. Consider that the ICON Mainnet Network is running already for some time and your validator is down or a new one is coming into play. Then, it would have to achieve the same blockchain state like other active validators. This will imply a very long time of synchronization, it is not efficient and issues might occur. Therefore, by using checkpoints and backups of the blockchain state, one may have a certain state of the blockchain and then sync from there. As a result, performance will be improved and the downtime that an existing validator would have will be reduced. This is exactly what we used and achieved with the support of the ICON team. A certain state of the blockchain was then deployed on the validator and once we started, it had synchronized very fast with the actual network state from that certain checkpoint in time.

By running on ICON Network since the beginning of the Testnet and now with 2 validators, we gathered a lot of experience and we tested multiple scenarios as well as designs. Also, we have the feeling that we contributed to the further development of the ICON Network and this is the best part of everything: adding extra value. Therefore, we think it is really important to be a part of a blockchain network as close to its initial generation as possible, and actively contribute to its further development and improvement. Sometimes such things are taken for granted, but are of core importance to the blockchain networks. This is a major topic on which Chainode Capital P-REP candidate team has been working in the past months, besides creating a portal for the entire ICON community.

Last but not least, we would like to thank Soo Kim and the whole ICON team for the support and interesting tech discussions. We will remain in contact and continue the exchange of concepts and ideas.

Social handles & Contact

Twitter: https://twitter.com/ChainodeCapital

Telegram: https://t.me/ChainodeCapital

E-mail: chainode.capital@gmail.com