Migrated on-premise mail to Zimbra on AWS with horizontal scalability — 0% data loss and minimal downtime across partitioned mailbox infrastructure email migrations.
Industry
Hosting & IT
Services
Technologies
Enterprise messaging provider partnered with Spectrum to address operational and technology gaps in hosting & it. Legacy on-prem mail could not scale with customer growth. A single cutover risked prolonged outage for thousands of mailboxes. Spectrum applied a phased delivery model — 4 months — aligning stakeholders, compliance needs, and production cadence. Since 2016, Spectrum has delivered similar programs with managed teams and fixed-cost options.
Legacy on-prem mail could not scale with customer growth. A single cutover risked prolonged outage for thousands of mailboxes.
On-prem mail infrastructure could not grow with tenant demand.
Big-bang cutover threatened prolonged outage for thousands of users.
Zero tolerance for message loss across heterogeneous mailbox sizes.
Partitioning and storage tiers were manually managed.
Three thousand mailboxes on aging hardware left the provider one outage away from churn. We designed for horizontal growth on AWS and moved users in waves — each wave proven with checksums before DNS switched.
Mailbox and message stores scale independently — large tenants no longer sit on a single noisy neighbor. Account partitioning spreads load; storage tiers match message retention policies customers already paid for. The design survived a simulated AZ failure in rehearsal: operations knew which DNS TTL to lower and which batch to pause before cutover weekend.
Big-bang was off the table. Each wave moved a defined tenant cohort with pre-migration sync, checksum validation on every mailbox, and a per-wave rollback script tested in staging. Support had a named owner per wave and a public status page for hosting partners. When one wave showed elevated latency, the next wave waited — data integrity beat schedule pressure.
DNS, mobile profiles, and desktop clients followed playbooks written with helpdesk input — not only engineering assumptions. A 24/7 war room ran through the first weekend with decision rights documented: who could extend maintenance, who could halt the next wave. User-visible downtime stayed within the window promised to enterprise customers in their contracts.
Mailboxes migrated
Data loss
User downtime
Mailbox and message stores scale independently on AWS with partitioned tenants — migration waves use checksum validation instead of big-bang DNS flips.
Separate tiers for mailbox, indexing, and blob storage let large tenants move without noisy-neighbor slowdowns. Auto-scaling policies follow daily send/receive curves per hosting partner.
Wave orchestration jobs perform pre-sync, delta sync, and checksum verification before cutover flags flip. Rollback scripts are tested per wave in staging with production-volume samples.
War-room dashboards show wave progress, error categories, and DNS TTL status. Helpdesk macros align with client reconfiguration steps for mobile and desktop profiles.
Spectrum addressed bottlenecks and compliance needs while keeping delivery incremental and measurable.
Delivered and measured in production with stakeholder sign-off.
Delivered and measured in production with stakeholder sign-off.
Delivered and measured in production with stakeholder sign-off.
Thousands of mailboxes moved in validated waves with checksum proof — hosting partners kept SLA credibility through controlled cutovers.
Mailboxes migrated
Data loss
User-visible downtime
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Typical engagement · 4 months
Assessment-led migration to cloud with phased cutover, security hardening, and DevOps pipeline establishment cloud migrations.
Logistics
Enterprise Cloud Migration
Full on-premise estate migrated to Azure including Intune device management, lift-and-shift of servers, and corporate data security controls cloud migrations.
Enterprise
Cloud-Only Azure Enterprise Migration
Cloud and on-prem spam filtering and inbox assurance — adopted by datacenters, hosting providers, and mass mailer platforms with automated multi-environment pipelines devops automation.
Cybersecurity
Email Security Application
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