Jin-ho Yun - Server Migration Consultant

Recommended expert

Frankfurt am Main, Germany

Experience

Feb 2024 - Dec 2024

11 months

Server Migration Consultant

Unknown Client

Linux server migrations: planning and implementing migration with SLES Linux, deploying VMs in VMware 8.0
Guiding colleagues in configuring Linux VMs in vSphere Auto Deploy
Application operations: ensuring smooth operation of applications on the migrated servers
Operations manuals: revising existing manuals, adding and creating new ones as needed
Reviewing service offerings: adjusting and optimizing the service package of external providers
Logistics software, RedHat Linux, Ansible, Confluence / Jira

Jan 2024 - Present

2 years 1 month

Bad Homburg, Germany

IT Consultant

HQ-Capital

Quandt Holding, finance investor since the mid-1980s, support for financial software
Support for branches in New York, Bad Homburg, Dubai, Singapore, etc.
Server and network monitoring using Open-Systems and Meraki Dashboard
Teams voice telephony consolidation meetings on optimization for the holding and its subsidiaries
Active Directory administration
VMware ESXi administration
Dell ESX Storage v3020 monitoring and administration
MS Server 2012 & 2019 administration, creating GPOs
Operations manuals: revising existing manuals, adding and creating new ones as needed
Monitoring with PRTG
Meraki cloud platform, Open-Systems network & security management, AD / Active Directory, MS Server 2012 & 2019, Dell ESX storage systems, PRTG

Oct 2022 - Dec 2023

1 year 3 months

Monitoring Engineer & Technical Contact for bahn.de

Deutsche Bahn

Member of the expert team, project “Vendo/Movas”
Operational responsibility for monitoring the train ticket system on bahn.de, specifically WEB
System runs on Amazon AWS, as containers / pods
System monitoring and documentation: continuous monitoring, analysis, documentation to ensure optimal performance & availability
Incident management, adapting processes and work packages for 1st level / 2nd level support
Optimizing end-customer communication in case of issues
Change management meetings, risk assessment and approvals of operational changes
Reviewing deployment results in GitLab, Assisify & Teams
Ticket management: tracking & communicating tickets to product owners, stakeholders, and development teams
Application management: partial responsibility for the web presence, ticketing systems, including web interfaces
APIs and microservices: error handling and dependency analysis of other domains
Test management and troubleshooting: monitoring during A/B, pre-live tests & commissioning of the new bahn.de website
Identifying and reporting critical issues / bottlenecks to stakeholders
Risk assessment and quality control: reviewing and evaluating feature requests and change approvals
Meeting moderation and stakeholder management: leading daily bug meetings & regular team meetings on automated tests in stages (test/int, acceptance, load, pres, pre-prod, prod)
Technical support for annual emergency drills
Collaboration with DB-Systel and exchange with stakeholders
Jira, Confluence, Instana (IBM), Graylog, Grafana, Splunk Enterprise, DB-Internal Tools, Assisify, GitLab, microservices, Docker, Confluence, Jira

May 2021 - Sep 2022

1 year 5 months

Senior Security Network Engineer

FI-TS (Finanz Informatik Technology Service)

Recertification & testing of firewall rules according to ECB guidelines after an audit for dwpbank via FI-TS
General connection analysis of software packages and related firewall rules
Random sampling analysis of server vulnerabilities using Jenkins: network configuration, port scans, weak passwords, insufficient protection of folders and files
Analysis and active participation: recertification of firewall rules
Consulting & IT security optimization: advising and implementing security rules from CyberArk to improve IT security level
Stakeholder management, ensuring communication and collaboration internally and with the client
Nmap, NetScan, Wireshark, ServiceNow (SNOW), Checkpoint and Cisco firewalls, FNT-Command, MS-Access, MS-SQL, Excel, Change, Bambi, ARS, CATS, Jenkins, Splunk, CyberArk, IP addressing concepts, Skype, ITIL, Skybox

Mar 2021 - May 2021

3 months

Product Owner & SRE (Site Reliability Engineer)

Commerzbank AG

Agile project management to develop an MVP
Building a financial transaction test bot with Dynatrace Synthetics
Product Owner: managing software development with Confluence & Jira; writing user stories
Collaboration with Dynatrace developers and guidance for programming tasks
Communication and reporting: regular meetings on project progress and creating PowerPoint presentations for management
Server control: access control via CyberArk on the jump servers
Problem management: planning developer meetings on solution approaches, compliance and regulatory topics
Support and monitoring: supporting the online banking platform DHB/CCS Meniga in the on-premises cloud
Teamwork in an international team with division of tasks in operations & monitoring
Agile project management, ITIL, user stories, epics, Jira, Confluence, IIS, Meniga, CyberArk, Windows 2012, MS Teams, PSD2, SCA, 2FA, PowerPoint

May 2020 - Mar 2021

11 months

Support Engineer / Application Support Software Engineer

Synamedia / Vodafone GigaTV

Supporting the solution provider in operating & monitoring IPTV and legacy TV services on the Vodafone / Kabel Deutschland platform
3rd level support: troubleshooting backend infrastructure in both AWS and on-premises environments
Infrastructure monitoring: monitoring the Kubernetes infrastructure using Grafana, Kibana, Prometheus, Uchiwa, and Pagerduty
Ticket management and middleware patching using SNOW & Jira; patching middleware; follow-up and tracking ticket handoffs
Legacy system support: working at the console, reading Linux server logs, config control and adjustments
Deployment and error analysis in the test environment as well as preliminary analysis for error qualification of Kubernetes nodes (Linux)
Supporting continuous improvement processes in software development with GitLab
Self-organization in a team of 3 support engineers
AWS S3, Docker, Kubernetes, Grafana, Kibana, Prometheus, Uchiwa, Linux, CentOS, Pagerduty, Teams, Slack, GitLab, ServiceNow, Jira, ITIL

May 2019 - May 2020

1 year 1 month

Test Manager & Testing of a Private Cloud Solution

FI-TS (Finanz Informatik Technology Service)

Testing an on-premises cloud solution on Hyper-V & MS Orchestrator for regional banks: HELBA, NordLB, BayernLB, LBBW, DEKA
Test execution and documentation: ongoing tests of the cloud solution across various stages including documentation of results
Communicating with the internal cloud development team & project managers about bugs
Reviewing and adjusting operational concepts
PAM access concepts: managing and planning automated service & admin accounts for secure access to the private cloud
Active participation in meetings to prepare application pilots for the financial institutions
System analysis using Splunk & communicating results to clients & involved teams
Reviewing and validating technical documents; creating technical one-pagers for each institution
Working on pre-tests for pilot applications & actively developing test automations
Documenting infrastructure-as-code errors & coordinating with developers
Hyper-V, MS Orchestrator, MS SCOM, MS VMM, MS SCCOM, MS Server 2012 & 2016, Red Hat 7, Docker, MS SQL, CyberArk, Splunk, GitHub, network, Squid proxy, VLAN, VM, Azure Connector, NetApp, SAP CATs, MS Visio, ITIL

Mar 2019 - May 2019

3 months

IT Consultant Windows and VMware

Enexion GmbH

IT consultant for the on-premises IT environment + VMware
Creating IT documentation of the current configuration and agreeing on solution approaches
General server administration
MS Active Directory, MS Server 2008 - 2016, ITIL, VMware ESXi, Hyper-V, Watchguard Firewall, Veeam

Feb 2017 - Mar 2019

2 years 2 months

Data Center Engineer, Linux & Windows

Dimension Data – VW-MAN MTB & MDT

Administration of 1400 Linux and Windows servers in the Dimension Data private cloud solution on VMware ESXi / Oracle OVM
Supporting the transition team in migrating Linux/Windows servers to the private cloud
Stakeholder management in the Partner Operating Center (POC) for clients & partners (SAP, web developers, network, security, storage)
Administration of VMs and on-prem servers including SLES SUSE Linux, OVM, Oracle Linux, Cisco UCS, Windows servers, Ansible & Jenkins
Managing jump server access with the PAM solution CyberArk; configuring session management, multi-factor authentication & auditing
System maintenance and monitoring of server health parameters
Backup and recovery for database and application servers using Commvault Simpana
Storage management: NetApp MetroCluster, scaling LUNs & volumes
Active Directory: administration of the production environment and maintenance of CMDB databases
Network and security: firewall management, creating rule requests, and support with network issues
Monitoring using Dimension Data's own solutions
Coordinating service providers: eShelter DataCenter, Cisco & NetApp
Creating & updating IT processes; maintaining the wiki on Confluence and SharePoint
Incident management & major incidents following ITIL
SLES SUSE Linux Enterprise Server 11 & 12, Red Hat, MS Active Directory, Microsoft Server 2008 - 2016, CyberArk, Ansible, Jenkins, ITIL, VMware ESXi, Hyper-V, SAP, Simpana, CommVault Backup, SC2 (VW-Service Center 2), Cisco UCS, eShelter

Feb 2016 - Jan 2017

1 year

Frankfurt, Germany

IT Service Engineer

Systrade GmbH

Supporting IT applications for medium-sized companies in the Frankfurt am Main area
IT project management and infrastructure management: about 8 ESXi servers with 30 VM Windows/Linux servers as well as physical servers and racks
Network architecture: planning, Cisco core switch upgrades
Team leadership and training: managing staff for setting up & rolling out customer notebooks and replacing network hardware
Hands-on work on Windows and Linux servers regarding installation, maintenance, and operation
Incident management and change approval; handling problem, service & change tickets
Revising and creating operational concepts and manuals
MS Active Directory, Exchange Server 2010 & Office 365, MS Server 2008 & 2012, VMware ESXi, Hyper-V, Linux, Windows Server 2012 & 2016, Watchguard Firewall, Backup Exec 2012 & 2015, Veeam, Cisco Catalyst 3850

Jun 2015 - Jan 2016

8 months

Deputy Project Lead in Network Architecture

Arvato Systems

Network planning & design for existing & new customers (end customer: Hettich), virtualized with Juniper SRX
Implementation of load balancers, proxies, SAP routers, TMG servers, web dispatchers, DNS, NTP, DHCP and Streamworks
Creating and managing project plans (MS Project, eWorks)
Leading stakeholder meetings and migrating machine networks with the network/security team
Implementing customer requirements on layer 2 & 3, including VLAN and IP network planning
Collaborating with Service Delivery, Service Management, Datacenter Run and build teams
VPN planning: setting up site-to-site and dial-in VPNs (IPSec)
Project effort estimation & escalation in case of bottlenecks
Troubleshooting using Graylog and requesting firewall rules
Script adjustments in Jenkins and change management in eWorks
MS Project, MS Visio, Graylog, VLANs, MPLS, VRF, FNT Command

Oct 2014 - Dec 2015

1 year 3 months

Frankfurt, Germany

Project Manager + IT Administrator + Technical Procurement

Wettmeister Service GmbH

Managing about 20 on-prem and VM Windows 2008/2012 + Linux servers
Backup monitoring, user & rights management
Ticket handling (incidents) according to ITIL: creating, analyzing, tracking and resolving
Network administration of Cisco switches & firewalls
Network switch from ADSL to VDSL at 30 sites
Deputy team lead in an IT rollout at 30 sites
2nd & 3rd level support for network and server issues
Planning and implementing VMware ESXi + SQL 2012
Administration of the VOD video wall solution "JustAddPower" with Cisco switches
Technical procurement for hardware, software, network & video wall solutions
Managing an IT budget of about €300,000
Documentation of operation manuals and wikis
MS Server 2008 & 2012, MS SQL 2012, Win 7, VMware ESXi, MS Active Directory, Cisco ASA 55xx, C2960 series, JustAddPower, ArcServe r15, Veeam, VOD

Nov 2013 - Oct 2014

1 year

Berlin, Germany

Migration Specialist, Service Desk Support

Vattenfall

Migration from Windows XP & Office 2003 to Windows 7 & Office 2010 for about 18,000 clients
Incident handling and administration of MS Server 2003/2008, Exchange Server and RAS
Win XP & 7, MS Office, MS Server, MS AD, Remedy, Dameware, RCMD, SD-Toolbox, Symantec Drive Encryption, SafeNet CryptoCard

Aug 2013 - Nov 2013

4 months

Kassel, Germany

1st & 2nd Level Support

Landeswohlfahrtsverband

Rollout migration support and incident management for 1,200 clients
Migration from Windows XP & Office 2003 to Windows 7 & Office 2010
Administration of MS Server 2003/2008, Exchange 2003/2007, Linux, Citrix Presenter & TS clients with Igel hardware
Win XP, Win 7, MS Office, MS Server, ACMP, ticket systems, Echolon, Citrix Presenter, Terminal Server

Aug 2006 - Mar 2011

4 years 8 months

IT, Server, and Network Administration

Hyundai-Kia Machine Tools Europe GmbH

Administration of MS Server services: DATEV, SAP and MS TS Server 2003
Supporting Windows XP clients
Managing the WAN line with Cisco firewall & routers on Dell servers
MS Server 2003, MS Active Directory, SAP servers, Cisco Pix 501, VPN, WAN, Dell PowerEdge 840

Jan 2006 - Dec 2008

3 years

Eschborn, Germany

External IT Consultant

Pantech & Curitel

Complete IT management and new setup of the European headquarters in Eschborn
Administration of Windows Servers, internet and WAN connections, as well as the telephony system

Sep 2005 - Jul 2011

5 years 11 months

IT Consultant

Pantos Logistics

Server management for server services including Exchange, TS & application servers
Operation of the WAN SDSL network
MS Server 2003, Active Directory, Bintec Firewall, IPSEC VPN, WAN, SDSL, DHCP, DNS, ML ProLiant and Dell servers

Apr 2003 - Dec 2015

12 years 9 months

Germany

Managing Director / IT Services for SMB

HAYU ITC GmbH & Co KG

Managed around 40 SMB clients in the Hesse region like Hyundai Mobis, Nexen Tire, etc.
Planning, implementation & administration of Active Directory and user support
Setup of leased lines, network cabling, VPNs and firewalls
Server management: file, backup, email, MS SBS servers
Support and setup of ISDN telephone systems
Administration of Windows Server 2000-2012, Exchange Server 2007, BlackBerry and NAS systems
Troubleshooting & repair of IT systems

Mar 2003 - Dec 2021

18 years 10 months

Frankfurt, Germany

IT Admin & IT Manager

Atlantic Integrated Freight (A.I.F)

Administration, planning & maintenance of IT & telephony systems for logistics sites
SBS 2008 server with Active Directory; support for 30 PCs at 2 locations
Administration and configuration of the Agfeo IT 200 phone system and Bintec firewall
Windows XP, Windows 7, MS SBS 2000-2012 servers, MS Active Directory, Terminal Server, Agfeo IT 200, Bintec Funkwerk VPN router, HP ProLiant

Mar 2003 - Dec 2013

10 years 10 months

Frankfurt, Germany

IT Consultant

Bank of Korea

Consulting and support for IT PCs and networks
Administration of the Siemens phone system & Cisco 2960 switch
Cisco 2960 switch, firewalls, Windows XP, Siemens telephony

Mar 2003 - Dec 2013

10 years 10 months

Instructor / Trainer

ML Consulting for the German Armed Forces

Teaching client-server administration nationwide
Network basics, TCP/IP, client-server, Active Directory

Jan 2003 - Dec 2013

11 years

IT Project Manager / Administrator

Eukor Car Carrier Inc.

IT relocation management: coordination of external vendors, construction supervision, SDSL provider
Dismantling and setup of servers, databases and network components in server racks
Administration of MS File, Exchange and Blackberry servers, and VPN users
Migration from MS-AD 2003 to 2008
Consulting and setup of Juniper SA 2500 VPN solution
Cisco Catalyst 2950, Networkbox, MS-AD

Aug 2000 - Apr 2003

2 years 9 months

Frankfurt, Germany

2nd Level Support NT & AIX Servers

Dresdner Bank

2nd level support for over 4,000 users
Notebook rollout and network support for over 13,000 devices
Use of PC-Duo, Hyena, Perl, and RAS support

Aug 1999 - Jul 2000

1 year

Düsseldorf, Germany

Remote

Third Level Support NT Servers & Terminal Server Setup

Henkel Düsseldorf (at Debis Systemhaus)

3rd level administration & support for about 100 NT, Novell, backup and antivirus servers
Domain consolidation and remote monitoring
Planning, setup & documentation of a training center with Terminal Server (Citrix Metaframe 1.8)
Environment: chemical industry and automotive (Mercedes-Benz steering systems)

Jan 1999 - Dec 1999

1 year

Owner / Founder

Yun IT Consulting

Founded an IT consulting business

Jan 1999 - Aug 1999

8 months

Hamburg, Germany

Trainer

LVA Rentenversicherung / Siemens-Essen

Conducted various training sessions on NT servers & workstations, administration, and networking basics
Training in the NT environment and networking

Skills

Several Years Of Experience As A Senior System Engineer In 2nd & 3rd Level Support
Application Support At The Os Level
I Bring 25 Years Of It Experience, Especially In Operations Across Diverse It Fields
Extensive Knowledge Of Various Monitoring Solutions
Experience In Private Cloud Solutions Based On Sccm Technology And Vmware
Aws Cloud Computing + S3 Know-how + Github Devops Tools
Teamwork: Very Good.
Personal: Open And Honest.
Learning Ability: Self-taught Acquisition Of New Techniques As Well As Through Training.
Others: Quick Understanding Of My Own Limits And Use Of External Support
Independence: I Look For Tasks On My Own And Develop Suitable Solutions.

Languages

German

Native

English

Advanced

Korean

Advanced

Education

Oct 1993 - Jun 1998

University of Applied Sciences Düsseldorf

Electrical Engineering / Microelectronics · Düsseldorf, Germany

Aug 1990 - Jun 1993

Municipal College and Technical School Duisburg North

State-certified Electrotechnical Assistant, university entrance qualification (Fachhochschulreife) · Duisburg, Germany

Certifications & licenses

Berater Für Elektromobilität Und Alternative Antriebe

Dekra

CyberArk Trustee

CNA

Certifed Novell Administrator

MCP

Microsoft Certified System Engineer

Adobe Sales Professional

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Christian Fritsch

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HQ-Capital

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Deutsche Bahn

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Commerzbank AG

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Synamedia / Vodafone GigaTV

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Enexion GmbH

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Systrade GmbH

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Arvato Systems

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Wettmeister Service GmbH

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Vattenfall

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Landeswohlfahrtsverband

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Hyundai-Kia Machine Tools Europe GmbH

External IT Consultant

Pantech & Curitel

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Pantos Logistics

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HAYU ITC GmbH & Co KG

IT Admin & IT Manager

Atlantic Integrated Freight (A.I.F)

IT Consultant

Bank of Korea

Instructor / Trainer

ML Consulting for the German Armed Forces

IT Project Manager / Administrator

Eukor Car Carrier Inc.

2nd Level Support NT & AIX Servers

Dresdner Bank

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Henkel Düsseldorf (at Debis Systemhaus)

Owner / Founder

Yun IT Consulting

Trainer

LVA Rentenversicherung / Siemens-Essen

Skills

Languages

Education

University of Applied Sciences Düsseldorf

Electrical Engineering / Microelectronics · Düsseldorf, Germany

Municipal College and Technical School Duisburg North

State-certified Electrotechnical Assistant, university entrance qualification (Fachhochschulreife) · Duisburg, Germany

Certifications & licenses

Berater Für Elektromobilität Und Alternative Antriebe

Dekra

CyberArk Trustee

CNA

Certifed Novell Administrator

MCP

Microsoft Certified System Engineer

Adobe Sales Professional

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