Linux Systems Administrator / DevOps Engineer
Role overview
Linux Systems Administrator / DevOps Engineer
Company: Dataphone Employment: Full-Time Location: Remote
About Dataphone
Dataphone operates a large-scale communications platform providing VoIP, PBX, Contact Center, SMS, AI voice, and business communication solutions.
Our production environment includes Linux servers, Node.js/TypeScript applications, PM2, NGINX, PostgreSQL, FreeSWITCH, OpenSIPS, Docker, monitoring systems, and multiple customer-facing services.
We are looking for a hands-on Linux Systems Administrator / DevOps Engineer who can take ownership of this infrastructure and help us keep it reliable, secure, and scalable.
Responsibilities
Linux Server Administration
- Manage production Debian/Ubuntu Linux servers
- Server provisioning, configuration, upgrades, patching, and hardening
- Manage CPU, memory, storage, processes, services, and networking
- Troubleshoot production outages and performance problems
- Manage SSH, users, permissions, sudo, and security
- Monitor server health and capacity
- Perform server migrations and maintenance with minimal downtime
- Maintain backups and disaster-recovery procedures
Node.js / TypeScript Application Infrastructure
- Deploy and maintain Node.js/TypeScript applications
- Manage applications running under PM2
- Troubleshoot application crashes and memory leaks
- Monitor PM2 processes, CPU, memory, restarts, and logs
- Configure PM2 clusters and process management
- Perform application deployments and rollbacks
- Troubleshoot application/server interactions
- Work with developers to resolve production issues
- Help establish standardized deployment procedures
You do not need to be a full-time application developer, but you must understand how Node.js applications run in production and be comfortable troubleshooting them.
NGINX
- Configure and maintain NGINX
- Reverse proxy configuration
- SSL/TLS certificates
- HTTP/HTTPS routing
- Load balancing
- WebSocket proxying
- Connection and timeout configuration
- Troubleshoot 4xx/5xx errors
- Configure security headers and access controls
- Review NGINX access/error logs
- Optimize NGINX for production traffic
PostgreSQL
- Manage production PostgreSQL servers
- Monitor database health and performance
- Troubleshoot connection issues
- Monitor CPU, memory, disk, locks, and connections
- Perform backups and restores
- Understand indexes and basic query performance
- Assist developers with database-related production issues
- Support replication/high-availability configurations
VoIP Infrastructure
- Maintain and troubleshoot FreeSWITCH
- Maintain and troubleshoot OpenSIPS
- Troubleshoot SIP registration and call-routing problems
- Analyze SIP/RTP traffic
- Use Wireshark, tcpdump, and sngrep
- Troubleshoot NAT, RTP, codecs, packet loss, and latency
- Monitor telecom infrastructure
- Assist with scaling and load balancing
Docker
- Manage Docker containers
- Troubleshoot containers that fail or restart
- Manage Docker networking and volumes
- Monitor container resources
- Maintain Docker-based production services
- Assist with containerizing additional applications
Monitoring & Logging
Maintain and improve monitoring across the infrastructure.
Experience with:
- Grafana
- Prometheus
- Loki
- Netdata
- Linux system logs
- NGINX logs
- PM2 logs
- Application logs
- PostgreSQL monitoring
- FreeSWITCH/OpenSIPS logs
The goal is to identify infrastructure problems before they become customer-impacting outages.
Networking
Strong understanding of:
- TCP/IP
- DNS
- HTTP/HTTPS
- WebSockets
- TCP/UDP
- NAT
- Firewalls
- Routing
- VLANs
- Public/private networking
- SIP/RTP networking
Automation
- Bash scripting
- Python and/or JavaScript/TypeScript scripting
- Ansible or similar configuration-management tools
- Git
- Automate repetitive server-management tasks
- Create scripts for monitoring, deployment, maintenance, and troubleshooting
Production Troubleshooting
This role requires someone who can independently investigate problems such as:
- Node.js application repeatedly crashing
- PM2 process consuming excessive memory
- NGINX returning 502/504 errors
- WebSocket connections dropping
- PostgreSQL connections becoming exhausted
- Server running out of disk space
- FreeSWITCH CPU suddenly increasing
- SIP registrations failing
- Calls connecting without audio
- OpenSIPS routing failures
- Docker containers repeatedly restarting
- Network latency or packet loss
- SSL certificate expiration
- High server load
- Application deployment causing an outage
The expectation is:
Detect → Investigate → Identify root cause → Fix → Verify → Document
Required Skills
Must Have
- 3+ years Linux administration / DevOps experience
- Strong Debian/Ubuntu experience
- Strong Linux troubleshooting
- NGINX
- Node.js production environments
- PM2
- PostgreSQL
- Docker
- Networking
- Bash scripting
- Git
- Monitoring/logging
- Strong production troubleshooting ability
Preferred
- FreeSWITCH
- OpenSIPS
- FusionPBX
- SIP/RTP
- Wireshark
- sngrep
- Prometheus
- Grafana
- Loki
- Netdata
- Ansible
- Redis
- WebSockets
- CI/CD
- OVH/Vultr/AWS infrastructure
Ideal Candidate
The ideal candidate is not someone who only knows how to follow a checklist.
We need someone who can receive a problem such as:
"The API is slow and customers are getting intermittent 502 errors."
…and independently work through:
NGINX → PM2 → Node.js → PostgreSQL → Linux → Network
to determine where the actual problem is.
You should be comfortable logging into a server, examining processes and logs, running diagnostics, making a controlled change, verifying the result, and documenting the solution.
Work Style
We are looking for someone who:
- Takes ownership
- Works independently
- Is a strong problem solver
- Doesn't require constant supervision
- Can work during production incidents
- Communicates clearly
- Documents changes
- Understands the importance of uptime
- Knows when to escalate an issue
- Continuously improves infrastructure rather than simply maintaining it
Technical Assessment
Candidates may be required to complete a practical assessment covering:
- Linux troubleshooting
- NGINX configuration
- PM2/Node.js troubleshooting
- PostgreSQL troubleshooting
- Networking
- Docker
- FreeSWITCH/OpenSIPS fundamentals
- Monitoring and log analysis
The assessment will focus on real-world troubleshooting and problem-solving rather than memorization.
Compensation
Compensation will be based on experience, technical ability, and location.
Candidates with strong production experience in Linux, Node.js/PM2, NGINX, PostgreSQL, and VoIP infrastructure may qualify for higher compensation.
