Migration Guide: How To Seamlessly Migrate Services To Local Servers In Taiwan

common reasons for migrating services to local servers in taiwan include: first, to significantly reduce access delays for users in taiwan and surrounding areas, improving page loading speed and user experience; second, to meet local data compliance and privacy regulations; third, to improve network stability and bandwidth controllability, especially for applications with high real-time requirements (such as real-time communications, online games, e-commerce); fourth, to use local cloud or idc service providers in taiwan to obtain technical support and operation and maintenance services that are closer to the local market.

technically, seamless migration can reduce tcp handshakes and routing hops, reducing packet loss rates; business-wise, localized deployment helps seo localization, smoother payment and logistics docking, and improves user conversion rates.

preparation work should cover five aspects: asset inventory, performance baseline, compatibility testing, backup plan and rollback plan, as well as migration window and communication plan. first list all dependencies (domain names, certificates, apis, third-party services, databases, caches, load balancers, etc.), and record performance baseline indicators (response time, qps, error rate) on the live network.

confirm the network egress, port policy, firewall rules and security compliance of the target environment in advance to ensure that the local server in taiwan can access all necessary third-party services or be allowed to access internal systems through the enterprise vpn.

before migration, be sure to complete a full backup and formulate executable rollback steps (including dns reverse switching, database rollback scripts, snapshot recovery, etc.), and reserve a sufficient time window for rollback drills.

the key to achieving seamlessness is to achieve smooth switching and minimize ttl impact. first complete the application deployment and testing on the target taiwan server , and use synchronization or mirroring to parallelize the old and new environments. set the dns record ttl to a smaller value (such as 60s) to take effect in advance to facilitate quick rollback during switching.

it is recommended to use grayscale/staged traffic switching: in the first stage, a small amount of traffic will be directed to the taiwan node to observe the error rate and performance; in the second stage, if it is stable, the proportion will be gradually increased until complete switching. cooperating with cdn, content caching can be done at the edge to alleviate the pressure on the origin site.

note that the ssl/tls certificate needs to be pre-configured on the new server and the link verified. if ip-based access control is used, a whitelist for the new ip needs to be applied for or configured in advance.

configure load balancer and health check policies (such as tcp, http status codes and response time thresholds) to automatically flow traffic back to the old node when the new node becomes abnormal, ensuring a controllable rollback.

common data synchronization strategies include master-slave replication (real-time off-site replication), double writing (the application layer writes to the old and new databases simultaneously and performs idempotent processing), and first using near-real-time synchronization tools (such as binlog replication, cdc tools) to synchronize historical data and incremental data to taiwan nodes. when choosing an option, weigh consistency, latency, and complexity.

if you use master-slave replication, you need to monitor the replication lag and ensure that the latency of the new database is within an acceptable range before switching. for strong consistency services, writing can be suspended at the moment of switching (short service stop) and a final synchronization can be triggered.

double writing or parallel writing scenarios must design idempotence and conflict resolution strategies (such as optimistic locking, globally unique id or timestamp conflict merging) to avoid data duplication or loss.

common faults include incomplete dns cache leading to access to the old site, certificate errors, database replication delays or interruptions, cross-domain/api authentication failures, static resource loading issues, etc. the order of troubleshooting is recommended to first confirm network connectivity (ping/traceroute), then check application layer logs and health checks, and finally check third-party dependencies (such as payment gateways, sns push).

1) network layer: use ping/traceroute and telnet to check port connectivity; 2) dns layer: confirm whether the local and public dns resolution results have been updated and whether the ttl is effective; 3) application layer: check error logs, slow queries and backend timeouts; 4) dependent services: check third-party callbacks and ip whitelists.

if a serious problem occurs and cannot be repaired in a short period of time, immediately implement a rollback plan: point the dns back to the old site, restore the database snapshot or restart the old service instance, and inform users of the expected impact and recovery progress. and perform root cause analysis afterwards to optimize the migration process to avoid recurrence.