Senior Systems Administrator

Job Summary:
Responsible for the building and maintenance of server hardware and software used to support client global service operations. Will work alongside application developers to assure optimal performance of production systems, and support their development resources. Support intranet resources for company-wide communication.

Essential functions:
Support mission critical FreeBSD and Linux systems; perform routine system administration functions including: OS tuning, performance monitoring, security monitoring, and system upgrades. Responsible for the installation, implementation, and management of all systems in client's remote data centers as well as our headquarters in Florida.Evaluate, recommend, and implement (as well as plan and document) enhancements to production systems and internal IT resources.Perform day-to-day system administration functions such as account creation, trouble tickets, server building and facilitating backups.Monitoring of all critical network and systems architecture.Assist with the administration and management of network security.Must be comfortable working long hours to complete projects.  24/7 on-call duties for directly managed projects and systems.  On-call cycle duties for other components of our operations.Must be willing and able to travel to datacenter locations for initial builds and expansion, if required.Assist IT staff in desktop support roles as necessary

Knowledge, skills and abilities / equipment:
Our systems are primarily UNIX-based, serving roles in both our hosting and network architecture. A strong understanding of UNIX and UNIX-like operating systems is required, with a focus on FreeBSD 6.x and the Centos Linux distribution running on i386 and x86_64 platforms.Knowledge of the broad scope of Network, Systems, and Information Security administration roles.Working knowledge of Cisco firewalls, switches & routers is required.A strong understanding of common desktop operating systems is also required to simplify client-server troubleshooting, when necessary. This includes Windows (XP, Vista) and Mac OS X, Linux desktopsMust have a strong understanding of application support in a distributed environment.Must also be flexible in programming languages and must have working knowledge in Perl and shell scripting.  C, C++, PHP, Python, a plus.  Must understand basic SQL and have experience using and administering MySQL database servers.Familiarity with full software development lifecycle experience is required, including but not limited to package management, patches, and software compilation. Strong familiarity with concepts such as RAID, hardware diagnostics, backups, replication, failure & recovery procedures are all required.Hands-on experience/knowledge with DNS and BIND, Apache1.3/2.2(server configuration, modules, tuning), FreeBSD(ports system), LAMP stack, rsync, MySQL, AWstats, Subversion, NFS, Samba, Sendmail/Postfix(along with anti-spam/fraud technologies such as SPF, Domainkeys, Sender-ID), SSL/certificate management and managing in-house Root Authorities, packet dump analyzers, stateful firewalls. Strong understanding of IP networking; understanding of how to isolate, diagnose, and resolve service delivery components (service delivery components include servers, networks, and applications); familiarity with the functionality, operating, and failure modes of key networking devices (routers, switches, firewalls, hardware load balancers); be able to identify networking as the potential cause of a service issue using server-resident tools to generate this data (tcpdump, ping, traceroute, etc.); familiarity in interpreting the output of these tools; familiarity with common network topologies, protocols, and tools; have some notion of common network security exploits -- and their remedies; understanding of troubleshooting at the packet level.Familiarity with Nagios, Mantis, Cacti, SmokePing a plus.Familiarity with cfengine, LDAP, and TACACS+/RADIUS is a strong plus.Familiarity with open source backup tools such as Bacula and rdiff-backup is also a strong plus.Experience building easy-to-use Web(PHP/Perl)/cli interfaces and tools for administrators and developers is a plus. Experience with server performance and trend recording tools such as rrdtool is a plus. Hands-on experience with Citrix/Netscaler application switches a strong plus.

Education and experience:
5+ years experience building and supporting mid to large server environments based on UNIX and UNIX-like operating systems in a Web environment. Certification is not necessary, but must be able to demonstrate in-depth knowledge in each of the required areas.