Scott M. Mcdermott

UNIX Systems & Network Administrator
available for contract or salaried positions

Professional Projects

Professional Projects

Grouped by category below are some of the projects I have worked on. The list is not complete, but serves as a good overview of my activities and duties.



Networking

  • full BGP ASN using two ISP homes at colo facility with full Linux rack
  • QoS over routed IPSEC for VOIP with several branch offices, offshore team
  • converge separate data, phone and video networks into one using IP techs
  • enterprise-wide Multicast routing and switching for multimedia with PIM-SM
  • extensive VPN and firewall ACLs for collab with offshore devs and partners
  • migrate VPN+firewall from Checkpoint FW-1 to Linux StrongSWAN and iptables
  • move inter-office WAN links from leased lines to IP routed IPSEC links
  • move from trunked, non-redundant to meshed, redundant LAN switching
  • implement EAP-TTLS WLAN NAPs with RADIUS backends authing out of PAM/LDAP

Mail

  • multi-site Postfix delivery routed directly out of user-configured LDAP
  • Qmail delivery using script-generated member lists from Netscape LDAP
  • Sendmail delivery out of flat, static alias files
  • implement semi-sophisticated UCE controls on Postfix mail exchangers
  • migrate SMTP routing from one-site MX (single hub) to multi-site MX/hubs
  • multiple authenticated SMTP techniques implemented for novpn offsite relay
  • migration of all tools that access mailstore from mbox to maildir format
  • most all IMAP and POP software packages run in production over the years

Services

  • run all setup and maintenance of hosted webapp/db instances for customers
  • custom Syslog strata, loghubs regex-filtered logs to readonly NFS exports
  • enterprise-wide fine-grained access control with POSIX ACLs, also to NT
  • join auth database silos at each site into distributed company-wide auth
  • migrate enterprise from Netscape/Solaris LDAPv2 to OpenLDAP/Linux LDAPv3
  • migrate SMB file and print services from NT to UNIX SAMBA
  • implement dynamic DNS via DHCP for enterprise-wide hostnames to all users
  • all-site traffic link statistics gathering via SNMP with MRTG, Cricket
  • network and service monitoring + alerts with Netsaint (aka Nagios)
  • split name service into routable & RFC1918 zones on separate name servers
  • reverse PTR delegation for DNS on both classful and classless nets

Automation

  • implement role-based server provisioning system over network using Cobbler
  • one-command instantiation of webapp customer instances (Apache/BEA/Oracle)
  • scripted, RAID-image based provisioning of different server classes
  • redundant, replicated directory services (DNS, LDAP, NIS, NT) company-wide
  • enterprise-wide by-arch automounting based out of NIS, later LDAP

Database

  • set up Oracle 9i RAC cluster on Veritas clustered filesystem
  • implement clustered PostgreSQL on DRBD using LVM snapshots for backups
  • track database maintenance and clone-to-dev events and store in database
  • work with postgres developers to fix regression bug in sql query optimizer

Hacking

  • implement shell script library for code reuse, highly factored scripts
  • standard parsing of shell script args, options, and rcfile, autogen usage
  • write syscall probe script using SystemTap to prove IO behavior of webapp
  • custom web UI for users to select from multiple webmails, IMAPs, POPs
  • hack open source web-based support tool to support LDAP logins
  • expose Spamassassin filter configuration via custom web interface to LDAP
  • custom web UI for config of email virus scanning using Vexira for UNIX
  • custom source hacks to Qmail to make email shunt for legal case
  • hack open source LDAP admin tool with customized web UI to full LDAP tree

Stuff

  • convert real machine to KVM instance using a loopback copy: kpartx, grub
  • maintenance of all development toolchains for all UNIX platforms
  • IO latency tools, disk top, find stuff with disk IO accounting tools
  • management of company SCM data in CVS and SVN, quasi-"release manager"
  • all UNIX hosts moved from pam_unix and NIS to pam_ldap with LDAP
  • migrate all Solaris-based services to Linux servers
  • scores of Solaris, HP-UX, AIX installs for developers
  • production Plone site for company information portal, import all data
  • pilots of many webmail, ticketing, bug tracking, CMS, timesheet packages
  • maintain and customize Bugzilla instance for use by development team

Administrative

  • "Agile Systems Administration" sprints, estimates, burndowns, feedback
  • several major IP/transport carrier negotiations (TWTC, Sprint, C&W)
  • work with Sprint engineers on QoS queueing policies for WAN links
  • consulting and recommendations to several small shops on contract basis
  • give regular IT user orientations for all new employees
  • work with several hosting providers to study cost scenarios for SaaS
  • perform evaluation and interoperation tests with NetApp Filer
  • formulate cluster split brain permutation matrices to rule out corruption
  • custom enterprise LDAP schema created, custom schema additions

Backups

  • Legato controlled AIT-2 changers at five sites
  • AMANDA controlled AIT-3 changers with holding disk and RAIT at three sites
  • sophisticated shell scripts for dump, rsync, RAID and LVM based snapshots
  • implement dedicated backup net to increase frequency and offload data net

Facilities

  • out-of-band server+power management via serial console, modem+network, PMU
  • maintain Nortel Meridian PBX, CAT3 cube wiring, toneouts, et cetera.
  • oversaw several office moves, 3 of these involving IT machine rooms/racks
  • wire a new ~65-person office by hand using CAT5 110-blocks, punchdowns
  • multiple data centers / colo sites / cabinets and racks wired