Single service comparison

Scope and front-end model diverge sharply. GCP offers a single global external HTTP(S) load balancer with anycast IPs that route to multi-region backends from one forwarding rule, while Huawei ELB is deployed per region (and per VPC) with regional load balancers; cross-region traffic requires multiple ELB instances fronted by Elastic IP, CDN, or Global Granny/DNS-based steering. Architects must replace GCP's global URL-map model with per-region ELB listeners plus DNS or CDN-level global steering, and there is no one-to-one parity object for a global frontend.

Control-plane objects and data-plane behavior differ. GCP decomposes configuration into forwarding rules, target proxies, URL maps, backend services, health checks, and NEG attachments with managed autoscaling via Managed Instance Groups. ELB uses load balancers, listeners, backend server groups (pools), health checks, and advanced forwarding rules; protocol support, header manipulation, weighted routing, and session stickiness map imperfectly, and ELB's dedicated versus shared load balancer instance types have distinct performance ceilings that GCP's fully managed proxy does not expose as selectable tiers.

Integration and operational responsibility shift. GCP ties load balancing to Cloud CDN, Cloud Armor, Cloud Run/NEG, and IAM via one declarative surface, with Google operating the data plane. ELB integrates with WAF, AAD (Anti-DDoS), Auto Scaling, Cloud Eye, and CTS, but the operator selects instance type, AZ planning, and quotas for security policies, certifications, and concurrent connections. Operational tooling, logging, and metrics APIs are not API-compatible, so Terraform/modules and SRE dashboards require rewriting rather than lift-and-shift.

Assess each GCP load balancer's scope first. Map global external HTTP(S) LBs and regional Network LBs separately: the former needs an architecture rework into per-region ELB (dedicated for heavy traffic, shared for low traffic) plus DNS or CDN-level global steering, while the latter maps more directly to a regional ELB L4 listener. Inventory forwarding rules, URL maps, backend services, health checks, NEGs, autoscaling groups, TLS certificates, and Cloud Armor policies, and decide per workload whether ELB alone meets the requirement or WAF, EIP, and AAD must be composed around it.

Re-architect configuration rather than translate it. Rebuild listeners and backend server groups in ELB, convert GCP URL-map path/host rules to ELB advanced forwarding rules (path, host, header, method matching), migrate TLS certificates to the ELB certificate store, and recreate health checks with matching ports and intervals. Port backend groups from Managed Instance Groups to Huawei Auto Scaling + ECS or to IP-as-backend groups for cross-VPC backends, and reattach any Cloud CDN or signed-URL delivery to Huawei CDN in front of ELB.

Validate thoroughly before cutover. Reproduce traffic tests with expected concurrent connections, new connections per second, and queries per second against ELB performance specs (hundreds of millions of concurrent on dedicated; 50,000/5,000/5,000 guaranteed on shared), confirm health-check failover across AZs, and verify WAF and AAD policies block the same attack patterns as Cloud Armor. Plan DNS cutover at a low-TTL record, keep GCP backends warm during the soak period, and stage rollback via DNS rather than stateful load-balancer migration since ELB has no import path for GCP LB configs.

Mind the cost and quota model change. GCP bills forwarding rules/proxies plus per-GB and per-request processed data, often with global anycast economy; Huawei ELB bills by load balancer instance spec (dedicated LCU/spec or shared) plus bandwidth and, if added, WAF, CDN, and AAD line items. Recompute TCO using peak concurrent connections, new-connection rate, request volume, retained logs, and cross-region/interconnect traffic, and request quota increases for ELB instances, listeners, certificates, and advanced forwarding rules in each target region before go-live.