What difficulties or system failures have you encountered regarding its availability during the project?

Projects related to system availability often encounter the following difficulties:

• Reliability issues: hardware or software failures lead to service downtime.
• Unexpected loads: a sudden increase in users can cause overload and availability drops.
• Code or configuration errors: bugs, incorrect settings can cause failures.
• Network problems: loss of connection between system components reduces availability.

To improve availability, the following are used:

• Database replication and clustering.
• Load balancing.
• Monitoring and automatic service recovery.
• Use of backup communication channels.

For example, in one project, during a database update without proper planning, the service was down for several hours, affecting users. Afterward, a hot standby scheme and phased updates were implemented, significantly increasing availability.