Corey Vincent Zelinski

Durham, NH USA

(603) 609-8510

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BRAINBENCH , Transcript ID 1115079 (2010), 22 certifications.

UNIX Systems Admin., Linux Systems Admin., Windows Admin., IBM AIX, Solaris 7, Solaris 8, Solaris 9, Solaris 10, Unix (General), Windows 2000, Server Admin., Shell Scripting, Disaster Recovery and Planning, Linux (General), DOS 6.22, Written English Grammar/Usage

N. ESSEX , 2009 - 2011. Philosophy.

NEWBURYPORT H .S., 2000 - 2004. General Studies; Adv. Spanish V & AP. John & Abigail Adams Scholarship.


Virtualization (VMWare, Xen), Portable shell-scripting, Systems and Protocol Stacks (e.g., TCP/IP), Solaris/Linux/UNIX (SVR4 and BSD derivatives, Debian/Ubuntu, RHEL, etc.), HTML/CSS, Textile/Sphinx (Documentation), Visual Basic 6, Apache/Nginx/IIS, Hardware/Software Installation and Repair, VMWare, Puppet, Citrix XenServer, Technical Writing, SAN Architecture, ZFS, PCI-DSS


Instabill Corporation. Greenland, NH. 2/2011 - Present

Senior Systems Engineer, Information Security Officer – Requirements analysis; systems design, testing, and implementation. Management of all physical and virtual systems (approx.. 115). Administration of POSIX/Sun Solaris, OpenBSD, Linux (Ubuntu, Debian, RHEL), Windows 2003, Windows 2008 R2, and other systems for a multinational, PCI-compliant Internet Payment Service Provider (IPSP). Administration and maintenance of the Payment Gateway, datacenter work across five locations (occasionally commuting to three of these), penetration testing, SAN design/engineering, hardening, system configuration and tuning, Virtualization (VMWare and Xen farms), provisioning, systems programming and shell scripting. Instabill is a Level-1 Service Provider in the credit-card industry focusing in offshore and high-risk card-not-present (CNP) credit-card processing. Policy drafting and approval; IT and Client Tech Support (CTS) hiring. Currently occupying the most senior IT position in the company; joined in early 2011 as a Junior Network Admin. Consistently good reviews and two promotions.

ACTV/Amherst Media. Amherst, MA. 1/2011 - 2/2011

Consultant - Assisted in provisioning and troubleshooting, TCP/UDP tuning, for a Unix-based streaming media server.

Eagle-Tribune Publishing Co. 9/2010-11/2010.

Solaris Field Deployment Engineer - Custom JumpStart install of POSIX Solaris 10 with Sun C compiler, custom environment, and software on two 1U rackmounts. Hardening and patching according to best practices.

Fowler Computer. East Rochester, NH. 2/2006 - 6/2010

Consultant (On-Call) - Hardware/software troubleshooting, installation, repair; upgrades, migrations, and OS deployments as well as tech support/housecalls.


Migration of the International Payment Gateway (IPP): Fresh redeployment under a new operating system (Solaris 10, patched and hardened according to the CIS Level-1 Security Benchmark), database migration (from MSSQL to PostgreSQL), database normalization, security overview on all layers of the OSI Model (redeployment of datacenter colocation rack, power calculations, systems design and deployment, hardening, Layer-2 switch configuration, creation of secure vLANs and RFC 1918 subnets, PCI ASV scans, service minimization, configuration of F5 ASM 1600 Webapplication Firewall, etc).

Redmine/ChiliProject Migration: Fresh redeployment, followed by iterative upgrade, of Redmine 0.8 and MySQL dB on Gentoo to ChiliProject 2.0 (fork) on OpenBSD, with proper separation of services (dB/webapp, etc). Skills needed: UNIX, Ruby-on-Rails troubleshooting

SAN Envrionment: Engineered Solaris ZFS SAN solution with portable, POSIX.2/XPG/LSB-compliant scripts to backup data (ZFS replication enabled, authenticated by SSH keys. Researched and selected hardware. Benchmarking and measurement of IOPS and performance, ZIL and L2ARC segregation on two sets of mirrored, Enterprise-class solid-state drives (SSDs). Tested and deployed in quick, short-iterative steps according to the Systems Engineering “V-Model.”

Skills needed: System V Bourne Shell, KSH, POSIX, Solaris 10, hardware engineering

newsyslog.c spinoff: Work on a proposed variant of newsyslog.c, editing C code, POSIX macros, testing-- in order to rotate directory trees similar to how regular files are rotated in /var/log. Skills needed: Low-level UNIX conceptualization, basic programming concepts, understanding of imperative coding paradigms

Amherst Media Project: Evaluating tunable kernel parameters, etc.

Solaris SPARC Deployment: Setup of Solaris 10 JumpStart Server and net-installation (followed by environment provisioning and hardening) to two SPARC Enterprise T1000s in an RFC 1918 subnet.

Centralized Logging Project: Testing and stack deployment for Graylog2, a syslog aggregation system (similar to Splunk, et al.) on a hardened/service-minimized Ubuntu server.

Intrusion Detection / File Integrity Checking: Deployment and configuration of OSSEC (tested on a VMWare virtual machine)

Network Documentation: Responsible for the official recension of the Network Documentation, as maintained under Revision Control in a Mercurial repository on a secure internal subnet. Network diagramming, inventory and description; responsible for the Disaster Recovery (DRP), Incident Response, and Breach/Contingency Response plans as well as all documents and guidelines relating to IT “Concept of Operations,” including practices and procedures for manual penetration testing in accordance with the PCI-DSS requirements.

PCI-DSS Compliance and Certification as a Level-1 Service Provider: Responsible for meeting the entirety of the Payment Card Industry Data Security Standard, v2.0 and passing an independent audit as approved by the PCI Security Standards Council and the Payment Brands (Visa and Mastercard).