Moved to Seattle and continue to explore things in DNS :)

Working hard and having fun! :)

Problem finder :)

Problem spotter and problem solver.Scaling out MySQL replication, duplicating databases for developers, tuning and optimizing MySQL servers, monitoring MySQL and other services with Cacti and Nagios. Dealing with InnoDB issues. Testing different versions and packages (native Debian dfsg and dotdeb) of MySQL server.Implementing security policies in production (reviewing current policies and security auditing, implemeting key-based SSH authentication with restriction by IP, installing fail2ban, updating Linux installations, configuring iptables, configuring snmp). Configuring DNS servers (bind) for local domains. Supporting existing mail servers (qmail and postfix). Configuring Apache for reverse proxying. Fixing any other issues.Security auditing and reconfiguring office gateways (Linux Debian), implementing security policies. Configuring OpenVPN for users. Making changes in Squid, shorewall and ISC dhcpd server. Security auditing office mail server (Zimbra).Setting up a dev server (git, gitlab, gitlab-ci).Setting up OpenLDAP and configuring “master-slave” replication of LDAP database. Supporting existing OTRS system and deploying and customizing new OTRS instance for accountants. Basic PHP scripting. Investigating network issues. Adding new checks to Nagios and Cacti, transferring Nagios and Cacti to new machines (along with their databases). Deploying new virtual Xen servers. Support of internal Wiki server. Investigating and fixing various other issues.Discussing and solving mail delivery issues with postmasters. Writing documentation and supporting developers. Prescreening and interviewing system admintrator candidates and mentoring junior system administrators.

Designing and implementing, installing, tuning and testing (stress and load tests) Sophos PureMessage mail system, designing and implementing mail scheme for outgoing emails.Deploying monitoring system (Zabbix). Installing OTRS ticketing system with AD authentication. Performing security audit, preparing mail system for PCI DSS certification. Fixing critical bugs and identifying root cause of issues, investigating web site failures and other production server issues, troubleshooting mail delivery failures, web server and MySQL database issues. Identifying improvements for existing tools and improving existing, creating various new scripts. Writing documentation. Supporting developers and troubleshooting issues with PHP code.

Deploying and tuning monitoring system (FreeBSD and later Linux, Nagios, munin), scripting routine tasks and automated existing manual processes (i.e. adding new customer; numerous monitoring scripts - checking balance, reporting from Nagios to pdf). Setting up and tuning office gateway (Debian Linux) - PPPoE connection to ISP, PPTP VPN server with AD authentication, implementing QoS for internet connection (iptables+tc). Setting up alternate internet connection for office network (Ubuntu Linux, 3G USB modem). Setting up and tuning filtering bridge on OpenBSD/Soekris. Administering Windows web and database servers. Deploying, administering and tuning Snort.New fault tolerance filtering bridge (CARP on OpenBSD - two independent servers in one case with a virtual IP managed by CARP), new monitoring system (Nagios), new open source network intrusion prevention system ( Snort). Internet gateway had been upgraded and fine tuned. New automated system for set up new clients. Migrating DNS servers from Windows DNS to BIND for scripting purposes, setting up split DNS with master-slave technology.

setting up the new server (Apache, MySQL, BIND, mail server – Courier IMAP + postfix), migrating to a different hoster, ongoing technical maintnance (forum engine upgrades, bug fixing), some new development (TV schedule, weather map).

I deployed and supported office Unix servers and infrastructure. Administered FreeBSD servers for corp network (DNS (bind8/9, customised bind9 for SPF support), ISC DHCP servers for multiple subnetworks with DHCP failover), and mail (Kerberos IV-5, majordomo, Cyrus IMAP/POP3, exim, sendmail, sendmail antivirus milters - drweb, clamav). Setting up a couple of mail relays for outgoing mail, builing cluster of antispam and antivirus servers for office use. Administered bunch of servers for antispam system Yandex.Spamooborona (Apache 1.3, MySQL). Designed and administered servers for version control support systems (FreeBSD, CVS, SVN, Apache 1.3 /2, PHP); developed and implemented a system of certificate-based authorisation; using jail for isolating separate repositories within one physical machine; using Apache+mod_auth_pam and samba+winbind for client authentication in Windows domain; using rsync schema for hot backup repository).Administered and fine tuned servers for the request tracker system (Debian Linux , OTRS, Apache, MySQL with replication), 2 bug tracker system (Debian Linux, JIRA) and 2 internal documentation conducting system (Debian Linux, Wiki). Designed and administered servers for IP-based block control system (Debian Linux, Apache, MySQL with replication). Analysis of sophisticated cases of blocking on Yandex.Mail. Managed DNS-based blacklists (RBL) for spam blocking. Supported open anonymous proxy-servers detection system. Issued certificates for corporate VPN access.New mail system for Yandex.Ukraine, new IP-based block control system, new fault tolerance system of outgoing mail, containing two part - separately for users and servers email. Expanding and scaling out SPF DNS. New fault tolerance DHCP scheme. New fault tolerance SVN cluster.

I supported office Unix and Windows servers and infrastructure (MS Windows 2000, MS ISA, FreeBSD, Squid), maintenanced of data storage fault tolerance system.

I supported office Unix and Windows servers and infrastructure(MS Windows 2000 domain controller, MS Windows 2003 servers), 4 MS SQL database servers, internet gateway and mail server (FreeBSD, SUSE Linux), maintained and supported for warehouse LAN - Novell NetWare 4), communications with branches (Frame-Relay), Internet connection setup and ISP interaction.Setting up MS SQL cluster, setting up mail system (sendmail+cyrus imap+drweb)

I supported office Unix and Windows servers and infrastructure (2 RedHat Linux servers (DNS, DHCP, sendmail, Squid, samba), 80 Windows workstations). new users registration procedure (bash scripting).

I supported office Unix and Windows servers and infrastructure (FreeBSD+samba file server, Windows workstations)Setting up samba for internal file sharing, setting up internet gateway and proxy server (squid).