About
I’m Dimitriy Leontev, a Network Administrator focused on Microsoft 365, identity, systems, infrastructure, and secure cloud operations.
I work in a public-sector IT environment where my responsibilities span Microsoft 365 administration, Microsoft Entra ID, Exchange Online, SharePoint Online, Microsoft Teams, Microsoft Purview, Active Directory, Windows Server and endpoints, networking, security, automation, documentation, and day-to-day IT operations.
What I enjoy most is working across the boundaries between those systems.
A problem that appears to be a Teams issue may actually involve identity, licensing, policy, networking, endpoint state, or the way a business process was designed. I like narrowing those problems down, understanding the underlying cause, communicating clearly with the people affected, and turning recurring issues into better standards, documentation, automation, or technical improvements.
What I Work On
My current areas of focus include:
- Microsoft 365
- Exchange Online, SharePoint Online, Microsoft Teams, and Microsoft 365 administration
- Identity
- Microsoft Entra ID, Active Directory, hybrid identity, authentication, MFA, Conditional Access, and access management
- Security
- Microsoft Defender, identity security, least privilege, Zero Trust principles, and secure administration
- Compliance & Governance
- Microsoft Purview, data classification, retention, sensitivity labels, and records-management considerations
- Systems & Endpoint
- Windows Server, Windows endpoints, Group Policy, Microsoft Intune, patching, configuration, and operational support
- Networking
- TCP/IP, DNS, DHCP, routing, switching, firewalls, wireless networking, and troubleshooting
- Automation
- PowerShell, Power Automate, workflow improvement, and reducing repetitive administrative work
- IT Operations
- troubleshooting, documentation, standard operating procedures, change planning, and continuous improvement
How I Approach IT
I try to look beyond whether a technical change simply works.
A production service also needs to be reliable, supportable, understandable, secure, and useful to the people who depend on it.
That means considering questions such as:
- How will this be supported after deployment?
- What happens when it fails?
- Can another administrator understand how it works?
- Can repetitive work be standardized or automated?
- Are permissions and administrative access appropriately limited?
- What privacy, security, accessibility, records-retention, or governance requirements apply?
- How will we know whether the change actually improved the service?
Working in the public sector has made those questions especially important. Technical decisions often need to account for security, privacy, accessibility, public records, records retention, procurement, operational continuity, and the needs of users with different levels of technical experience.
Professional Focus
I am continuing to deepen my expertise in Microsoft 365 and Microsoft Entra while expanding my systems, cloud, automation, and infrastructure engineering capabilities.
My long-term interests are in roles where Microsoft cloud services, identity, infrastructure, troubleshooting, security, and customer experience intersect.
The projects and articles on this site document that work through sanitized technical examples, lab environments, reusable frameworks, and lessons learned. I intentionally avoid publishing organizational data, production configurations, user information, credentials, or security-sensitive details.
Certifications
- Microsoft 365 Certified: Administrator Expert
- Microsoft 365 Certified: Teams Administrator Associate
- Microsoft 365 Certified: Endpoint Administrator Associate
- Microsoft Azure Fundamentals
- Microsoft 365 Fundamentals
- Microsoft Security, Compliance, and Identity Fundamentals
- Cisco Certified Network Associate
- CompTIA Security+
- CompTIA Network+
- CompTIA A+
- AWS Certified Cloud Practitioner
- Google Cloud Digital Leader
- Google Cloud Generative AI Leader