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Linux/unix Senior Systems Administrator Resume

Cleveland, OH


  • 8+ years of experience in administering Unix (IBM AIX, HP-UX, Solaris, FreeBSD), Linux (RedHat, CentOS, Gentoo and openSUSE) and Windows Servers for Research and Enterprise applications.
  • Well experienced in hands on, Kickstart (PXE) and Jumpstart installation of various fully and mostly POSIX compliant systems like AIX 5L & 6, HP-UX, Solaris 9 &10, FreeBSD 7 &8, RedHat 4,5 &6, CentOS 5 &6 , openSUSE 11 & 12 and Gentoo.
  • Very strong understanding of Linux/Unix Kernel internals, Security, Patching and overall implementation.
  • Hands on experience in virtualization technology with VMware (ESX/ESXi, vCenter, vCenter Converter, vSphere, vMotion), Xen and MS Hyper-V hypervisors.
  • Hands on experience in various direct attached and networked connected storage concepts like LVM,NFS, SAMBA, RAID 0/1/5, SAN(Fibre Channel, iSCSI) Filers like NetApp and HP EVA storage.
  • Experience setting up blade servers from various hardware suppliers like DELL (PowerEdge), HP (ProLiant G7 & G8), IBM BladeCenter and Sun Fire and Enterprise servers (X-series and T-series).
  • Experience and good understanding of different networks (LAN, WAN and VLAN) in different topologies and devices like Routers, Switches and Load balancers (Hardware and Software) like F5, Barracuda,Zeus, Radware and Perlbal.
  • Hands on experience installing, configuring, authoring and managing modules and manifests of configuration management tools like Puppet and CFEngine.
  • Well experienced in the installation, configuration and troubleshooting of various HTTP and HTTPS web and application servers like Apache, Nginx, Lighttpd, Apache Tomcat, IIS, JBoss, Websphere and Perlbal.
  • Hands on experience and solid skills in installing, configuring and supporting most of the leading database servers like ORACLE, MySQL, SQL Server and PostgreSQL and a very small experience with DB2 and Teradata.
  • Experience determining backup methods, policies and retention policies for disaster recovery, implementing automated NetApp Snapshots, disk backups for applications as well as databases and hands on experience in NetApp Snapshot, SnapDrive, SyncMirror and SnapVault.
  • Experience in the installation of various application and data cache servers and application accelerators like Varnish, Memcache and Squid.
  • Solid understanding of OSI model, layers and various protocols like TCP/IP, UDP, TLS, SSL, HTTP, HTTPS, FTP, SFTP, SMTP, POP, IMAP, SSH, LDAP( Add, Bind, Delete and Modify).
  • Experience installing, configuring and managing in house domain name servers (DNS) with powerDNS, BIND and also in using Dnsmasq to replicate production environment in the same data center to avoid IP/Name conflicts.
  • Very good understanding of Linux/Unix utilities like sar, iostat, vmstat, netstat and strace to troubleshoot performance issues and problems.
  • Excellent scripting skills in Shell (bash, ksh), Perl and entry level skills in Ruby and Python.
  • Hands on experience installing and configuring and managing various monitoring tools like Nagios, Cacti, Ganglia and enterprise monitoring solutions like Groundworks.
  • Hands on experience installing, configuring and managing various mail servers like Sendmail, Postfix and Zimbra.
  • Experience configuring package servers and managing the source Git repositories to make automated builds triggered by certain criteria and managed package distribution upon build to distributed package servers.
  • Very good understanding in the concepts and implementation of high availability, fault tolerance, fail over, replication, backup, recovery, Service Oriented Architecture( SOA) and various Software Development Life Cycle(SDLC) methods.
  • Experience in setting up infrastructure on private and shared resource environments such as clouds like Amazon EC2, Rackspace and Centurylink/Savvis and opensource cloud solutions like OpenStack.
  • Very good understanding of Service Oriented Architecture (SOA) concepts and its implementation.
  • Excellent skills in problem solving, analysis, communication and documentation.
  • 24/7 support for issues arising in production for mission critical and enterprise level applications.

Technical Skills:

Operating Systems: Linux (Red Hat, CentOS, SUSE, Gentoo, Ubuntu and Fedora), UNIX (OS X, FreeBSD, OpenBSD, Solaris, HP-UX, IBM AIX), Microsoft Windows Server 2003&2008

Hardware: DELL (PowerEdge), HP (ProLiant G7 & G8), IBM BladeCenter, Sun Fire X-series and T-series Enterprise Servers

Scripting: Shell (bash, ksh), Perl, PHP, Ruby, Java, PL/SQL, SQL, C, C++ and Visual Basic.

RDBMS: ORACLE, MySQL, PostgreSQL and MS SQL Server


Web Server: Apache, Nginx, Lighttpd, Apache Tomcat, IIS, Perlbal, HAProxy and JBoss

Virtualization: VM Ware ESX & ESXi, vCenter, vCenter Converter, vSphere, vMotion, Hyper-V, KVM, Qemu and Xen Hypervisor

Storage: LVM, SCSI, SATA, Ext 2, Ext 3, Ext 4 and NAS(NFS, SAMBA, RAID 0/1/5) and SAN(iSCSI, FibreChannel) NetApp filers.

Performance: Apache Bench, HTTP Load, MySQL slap and PHP Unit

Tools: GNU make, awk, sed, top, iostat, vmstat, netstat, sar, ps, dig, strace, tcpdump, lsof, yum, rpm, ping, lookup, trace, tar and parted.

Other: Varnish, Squid, Memcache, SSL, Solr, PowerDNS, openLDAP, Puppet, CFEngine, Janus, Jenkins, Vim, GPG, AWS (EC2, S3), VSFTP, Git, Liquibase, SVN, CVS, CPAN, Heartbeat, Nagios, Cacti, Ganglia, Postfix, Zimbra, SendMail and Jira.

Professional Experience:

Confidential, Cleveland, OH

Linux/Unix Senior systems Administrator

Duties and Responsibilities:

  • Redesigned the entire local infrastructure at Urbancode for optimization of both hardware and software resources.
  • Planned and implemented the migration of the entire infrastructure on to power 9 network from UrbanCode to IBM as part of acquisition and transition.
  • Created two VMware 5.0 ESX and ESXi clusters with the available hardware and configured storage and networking for the local development and testing environments.
  • Performed Security remediation and hardened OS and the entire application stack by following guidelines as dictated in the RISA Security remediation on existing and newly built RedHat, CentOS, Solaris and windows machines.
  • Created VMware ESX 4.1 and 5.0 templates for RedHat 5 & 6, CentOS 5 & 6, Solaris 10 & 11 and Windows Server 2003 & 2008.
  • Upgraded over couple of hundred CentOS and RedHat servers from 5 to 6 with out causing any issues with applications and made a smooth transition of services running on them.
  • Involved in Solaris 10 Upgrade of more than 100 servers utilizing Jumpstart, Live upgrade and DHCP/WAN boot installation technologies.
  • Migrated VM's over versions of VMware ESX clusters(V2V) and converted physical machines to VMware server VM's (P2V) using VMware VCenter Converter.
  • Installed and Configured hundreds of Virtual and Physical machines for development and testing of various UrbanCode products like Ubuild, Urelease and Udeploy and administered the entire infrastructure.
  • Scripted and deployed several shell-scripts for automation of job processes (e.g., daily extracts of UNIX environment , hard-disk failures monitoring, DNS monitoring, Quality-Assessment and Operational Readiness of newly built servers)
  • Installed and configured various database servers like Oracle 11g, DB2, PostgreSQL and MySQL and performance tuned all the database servers.
  • Installed and configured various web servers like Apache, Apache Tomcat and websphere.
  • Installed and configured DHCP, DNS (BIND), OpenVPN and Wifi (Radius) servers, Vyatta routers and CISCO switches.
  • Installed and configured OpenLDAP server for internal authentication and tied the LDAP server to Active Directory server on power 9 Network for developer access from the internal isolated network.
  • Responsible for writing and maintaining the application health check scripts and disk cleanups.
  • Responsible for backing up application and operating system logs and rotating them on a timely basis.
  • Involved in preparing Root Cause Analysis (RCA) reports for all critical issues, analyze and propose solutions to fix them to all the teams involved in the process.
  • Tuned Kernel, TCP parameters and the application stack for optimized performance and as part of application requirement.
  • Participated in weekly acquisition/transition meetings and discuss problems/solutions and document them as part of the process of integration.

Confidential, Buffalo, NY

Linux/Unix Senior Systems Engineer

Duties and Responsibilities:

  • Administered the entire heterogenous environment comprising of Solaris, FreeBSD, RedHat and CentOS.
  • Built Physical and Virtual machines (VMware ESX, ESXi & Xen Hypervisors) and configure a bare bones machine to become a fully functional member of production, development and test environments.
  • Authored in house scripts to deploy event triggered kickstart installations of VM's from test and dev environments to facilitate easy replication of production instances in testing and development.
  • Managed patching and upgradation of Operating Systems and other software to take care of security vulnerabilities and compliance.
  • Tuned kernels and other software on RedHat, CentOS and Solaris to optimize resource utilization and minimize
  • Configured and managed storage to support infrastructure with LVM, NAS (NFS, SAMBA) and NetApp SAN (iSCSI) filers.
  • Configured and managed the whole array of Web, Database, Mail, Static Asset, Cache, Git, FTP, LDAP, DNS and Name servers with Puppet or CFEngine.
  • Installed, configured and managed access across the organization with LDAP (openLDAP) and MS Active Directory.
  • Installed PowerDNS, migrated BIND Zones to PowerDNS with SQL import.
  • Installed Dnsmasq and replicated entire production environment in the same data center with a separate network to allow development and release teams to simulate code releases and production updates.
  • Monitored server and application performance & tuning via various stat commands (top, sar, iostat, vmstat, netstat, mpstat, prstat, nfsstat, prtconf, prtdiag, iostat, top, printmgr, hpimliview, dmidecode, smc etc) and tuned I/O, memory etc for SUN Solaris and RHEL Servers.
  • Installed and configured centralized Git servers that host thousands of repositories both internal and external and established secure access.
  • Installed Hudson/Jenkins on build servers that trigger automated builds from hooks setup on git servers.
  • Installed the Java cluster with JBoss to serve high power applications and Jetty/solr to serve a highly indexed customer facing search data.
  • Worked with availability engineering team to establish performance benchmarks and tune the OS and other S/W on the entire infrastructure across all the clusters to be highly available and resource optimized.
  • Implemented High availability and disaster recovery with multiple data centers and plan rerouting of a fraction or entire traffic to a designated data center to avoid down times and SLA impacts.
  • Implemented backups with NetApp Snapvault and documented backup and retention policies, backup procedures across the whole infrastructure and planned for Disaster recovery with Snapmirror across data centers.
  • Worked with Database, Network and Development teams and provide expertise in determining the technical strategies and system architecture for initiatives and infrastructure delivery.
  • Took part in planning and building release and deployment tools that are used internally on daily basis for deploying code to hundreds of servers.
  • Built and delivered cross functional tools for teams that need immediate solutions for unforeseen problems.
  • Troubleshooted and debugged environmental and infrastructural problems found in the production and non-production environments.
  • Supervised nightly release activities from systems engineering stand point to facilitate code push to hundreds of machines in various data centers within strict deadlines.
  • Took part in architectural and engineering meetings to plan and integrate new systems and to service the existing infrastructure.
  • Installed and managed confluence API and its sub API's like JIRA (ticketing system), Wiki (custom wikipedia).
  • Shared the on-call rotation for 24/7 availability to handle production environment problems.

Tech Summary: FreeBSD, Solaris, Red Hat, CentOS, F5, Radware, Apache, Lighttpd, Nginx, Jetty, JBoss, MySQL, MongoDB, PostgreSQL,VMware ESX, ESXi, Xen, Varnish, Squid, Memcache, PHP, Perl, Java, Python, Puppet, CFEngine,Maven, Hudson, Jenkins, BIND, PowerDNS, DynECT, openLDAP, MS Active Directory, MS Exchange Server, Nagios, Cacti, Groundworks, Git, CVS, Liquibase, Solr, NetApp SAN and NAS

Confidential, Washington DC

Linux/Unix Systems Administrator

Duties and Responsibilities:

  • Installed and configured VMware ESX, vCenter servers and configured storage and networking.
  • Setup a couple of hundred VM's running CentOS to be used for web, database, application, mail, ftp,monitoring and git repositories.
  • Migrated physical boxes to virtual machines (P2V conversion) with VMware vCenter converter.
  • Managed Adding and removing data stores and ESX hosts through vCenter.
  • Performed OS Hardening to reduce security vulnerabilities and tuned kernel for efficiency.
  • Installed Apache, Nginx, Lighttpd and Perlbal to serve HTTP and HTTPS requests and tuned them.
  • Installed and configured web and database caching with Memcache and Varnish.
  • Installed and implemented NAS with RAID 1 and RAID 5 configurations.
  • Monitored load and performance on the infrastructure and added capacity as needed.
  • Automated disk backups and retention with shell/Perl scripts.
  • Installed and configured IBM AIX and Websphere server to support of an array of websphere middleware applications.
  • Installed and configured Oracle 10g RAC and MySQL 4 cluster to serve internal tools and support external API's.
  • Performed hot and cold backups of different types of nodes in the infrastructure and planned for disaster recovery
  • Setup DNS and LDAP servers for the entire infrastructure support.
  • Installed and configured DNS servers with BIND and setup Zones.
  • Installed and configured mail servers with Sendmail.
  • Installed and configured some very public facing application servers on amazon EC2 instance.
  • Managed the entire infrastructure's copnfiguration with puppet by setting up puppet master and slaves.
  • Setup and configured yum servers to serve the entire array of CentOS boxes.
  • Monitored performance with linux utilities like sar, iostat, vmstat, mpstat, netstat etc.
  • Installed and configured the entire LAMP stack across the organization.
  • Authored Shell/Perl scripts for automating daily tasks and installed crontab on various user accounts on various types of machines across the infrastructure.
  • Implemented caching with Varnish and memcache to support application cache as well as static cache.
  • Setup Perlbal a perl based reverse proxy s/w load balancer to balance and bounce requests among web, database and memcache servers.
  • Installed, configured and managed monitoring with Nagios and the Cacti servers.
  • Worked with various hardware vendors to troubleshoot hardware and firmware problems.
  • Supported the Systems infrastructure with 24/7 availability and helped networks and database teams to troubleshoot production issues without down time.

Tech Summary: CentOS, IBM AIX, F5, Perlbal, Apache, Lighttpd, Nginx, Websphere, Oracle, MySQL, VMware ESX, Varnish, Memcache, PHP, Perl, Python, Puppet, Hudson/Jenkins, PowerDNS, openLDAP, Nagios, Cacti, Git, CVS, Liquibase, Solr, RAID, NFS.

Confidential, Norfolk, VA

Linux/Unix Systems Administrator

Duties and Responsibilities:

  • Administered the entire IBM AIX, HP-UX, Solaris, RedHat and MS Windows server2008 that serve the faculty, student course and lab work as well as research facility servers.
  • Performed mass installation of RHEL with kickstart installation.
  • Installed and configured Oracle (kickstart), MySQL server clusters and tuned them.
  • Performed Kernel tuning and OS hardening and patching.
  • Installed and implemented LVM, NAS storage with NFS, RAID 0.
  • Setup and configured the entire web pool with Apache/Nginx which serves the department portal as well as the university records.
  • Installed and configured sendmail and MS Exchange servers.
  • Automated NFS mount point checks and mounting and unmounting operations.
  • Installed and configured DNS servers with BIND and setup Zones.
  • Performance tuned the entire web pool and database cluster.
  • Installed and configured s/w load balancer (zen) as well as the hardware load balancer (Barracuda).
  • Performed snapshots and maintained backups of the machines as well the databases.
  • Setup storage and networking for the entire application server pool and cache pool
  • Setup Ganglia and managed monitoring for the entire infrastructure.


Associate Linux Systems Engineer

Duties and Responsibilities:

  • Installation, configuration and maintenance of production and UAT environments.
  • Provided 24/7 on call support for a cluster of over a hundred Red Hat & SUSE Linux servers.
  • Setup the required infrastructure in a virtual environment and maintained it.
  • Configured OpenLDAP to provide centralized authentication for all the physical and virtual machines.
  • Respond to tickets opened by routine alarms and network issues.
  • Served as the point of contact for the offshore teams that required access as well as technical resource.
  • Authored scripts for displaying the Nagios monitoring results in a very user friendly way the NOC team .
  • Troubleshoot and fix the issues arising from any where in the infrastructure with the help of associated teams like Networking, Database Administration and DevOps.
  • Configure the UAT environment with the application stack requested and configured them to emulate the production in all aspects for a full fledged internal testing.
  • Configured the internal DNS server and DHCP server.
  • Remotely accessed the customer networks following customer-specific procedures to confirm connection and power.
  • Documented all technical inquiries, develop and review content for knowledge base
  • Installation and configuration of RPM packages for upgrades using YUM server.

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