• AWS Cloud Computing, Google Cloud Platform, Oracle Cloud Infrastructure, Digital Ocean Cloud Computing
• Kubernetes, OpenShift(OKD4), docker
• Terraform/Ansible/Helm/Argo CD
• HashiCorp Vault
• Jenkins/GitLab/Bitbucket/Concourse CI
• Kafka/RabbitMQ/Redis/Git
• Elasticsearch, Kibana, Logstash, Fluent-bit
• MongoDB/Cassandra
• Monitoring: Prometheus with Grafana, Zabbix, Nagios, Cacti
• Routing and switching: STP (RSTP, MSTP), VLAN, switch clustering (VSS from Cisco, IRF from HP, Virtual Chassis from Juniper), Policy Base Routing (PBR), Static routing, Dynamic routing (RIP, OSPF, BGPv4); Multicast routing (PIM (dense and sparse mode))
• IT security: Microsoft TMG, Checkpoint Security Gateway, FreeBSD PF, Linux IPTables
• Servers OS: CentOS, Coreos, Debian, Ubuntu, FreeBSD etc
• Databases: MySQL (Galera XTraDB cluster), PostgreSQL
• Infrastructure: NAS, SAN, LTO, FC, iSCSI, NFS, ESX, Hyper-V, LAN, WAN
• Python development: OOP, Flask