Sadman Hasan Miraj

Resolved 200+ client tickets across 10+ countries, troubleshooting VoIP issues including call failures, SMS delivery errors, voice quality degradation, and recharge failures with a 95% first-response resolution rate. Installed, configured, and maintained REVE Systems' iTel Switch (softswitch) and iTel Mobile Dialer for 15+ global clients, reducing deployment time through standardized setup procedures. Administered 10+ Linux production servers using grep, sed, awk, ps, top, rsync, scp, and vi for real-time diagnostics, log analysis, and proactive maintenance, contributing to 99%+ server uptime. Executed 500+ MySQL queries for database monitoring, troubleshooting, and client data verification in a production telecom environment, identifying and resolving data inconsistencies within SLA. Monitored server health, storage capacity, and uptime across production environments; escalated and resolved 30+ incidents including server downtime, storage saturation, and server migration tasks. Coordinated online support via ticketing system, WhatsApp, Microsoft Teams, and phone within a cross-functional team of 22+ engineers across Bangladesh, India, and Pakistan following Agile workflows.