Plato

Login to Plato


This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Don't have an account? 

Back to resources

Migrating a Legacy Service: A Lesson in Eng/Ops Collaboration

Collaboration

18 November, 2020

Jackson Dowell, Engineering Manager at Asana, discusses how he approached legacy service migration by stabilizing the existing stack and getting Engineering and Operations to work together to address the underlying problems.

Problem

I was managing a team at LinkedIn that inherited a set of legacy Python services that we were part-way to migrating to a new Java microservices stack. In the past, Engineering was focused on building the new stack and running the data migration while Operations was siloed and responsible for keeping the existing software alive - including some wild hacks and constant pages. Ultimately the existing Python services were causing regular production outages and the migration plan failed to address the underlying technical issues, so I needed to reprioritize and change how engineering and operations were working together.

Actions taken

Our NYC-based team flew to California to do a handoff with the existing development team because the project was in flight. I had my engineers pair with the team that was actively working on the migration, taking small tasks across both systems and getting mentorship so we could learn how to confidently make and release changes.

As part of the handoff, I facilitated meetings between SRE (Site Reliability Engineer) leads who were transferring ownership of this project. Participating in their exchange helped me compile the full state of the world of the software that was operating in production, including the existence of a script that rebooted hosts stuck on failing jobs that executed at least once a minute across the whole fleet.

During the first week we took over, there were two outages caused by that piece of software. In the first instance, I had a member of my team pair directly with the engineer who investigated and resolved the incident. In the second case, the engineer on my team was able to take the lead and, supported by another person on the team, resolve the problem. I noted commonalities between both incidents and action items we would take to prevent the problem from recurring.

Once I had a full understanding of the existing system and the migration plan, I wrote up an analysis that I shared with my manager and the team of leads in New York to secure buy-in for a process called code yellow -- active feature development would pause until the operations were stabilized to the point that both SRE and Engineering were satisfied. I defined the exit criteria for code yellow, which included completing action items from the past incidents, introducing connection pooling and connection limits to the database (preventing cascading failures), and introducing a paging rotation in engineering to support future outages. We targeted a two-week window and were able to exit code yellow on time.

Lastly, I worked with my Tech Lead to revamp the migration plan to address failures in long-running jobs in the first milestone and to improve the safety of the data migration. We communicated the new plan. then held daily standups where engineers and SREs worked together to balance addressing short-term stability issues and investing in the migration to get to a long-term safe and scalable state.

Lessons learned

  • Having Engineering and Operations both take responsibility for solving incidents (including being paged) instilled a culture of caring for the reliability of our software. The engineering team translated that into excitement for discovering and remediating existing bugs and producing high-quality designs for the new system. The SRE team also felt supported and collaborated regularly to define requirements for how the new system would behave and solve current problems.
  • I got positive reinforcement for questioning the existing plan given new information. Even though it was controversial to delay our migration, we were ultimately able to provide better service to our customers and members, and we learned a lot about how to design our system to scale effectively.

Discover Plato

Scale your coaching effort for your engineering and product teams
Develop yourself to become a stronger engineering / product leader


Related stories

Holding Partner Teams Accountable
16 June

Manzar Kazi, Software Engineering Manager at LinkedIn, speaks of his experience of holding a partner team accountable with whom his team had multiple dependencies.

Deadlines
Internal Communication
Collaboration
Manzar Kazi

Manzar Kazi

Software Engineering Manager at LinkedIn

How Context Evolves as You Advance as a Manager
17 June

Heiko Reintsch, Head of Product at GetYourGuide, bears witness to the unifying power that a comprehensive, company-wide vision has over a large team of individual contributors.

Product Team
Collaboration
Sharing the vision
Team processes
Heiko Reintsch

Heiko Reintsch

Head of Product at GetYourGuide

How to Delegate Effectively
17 June

Tushar Dadlani, Director of Engineering at Standard Cognition, was far from a natural delegator when first starting out in management.

Delegate
Collaboration
Ownership
Tushar Dadlani

Tushar Dadlani

Director of Engineering at Standard Cognition

Testing, Learning, and Improving: Building a Successful System Progressively
17 June

Rohan Kulkarni, Engineering Manager at Expedia, shares his first significant triumph implementing a new system of cross-functional cooperation across an entire organization, testing, learning, and improving over the course of three quarters.

Collaboration
Team processes
Rohan Kulkarni

Rohan Kulkarni

Sr Engineering Manager at Expedia

Balancing Expectations of Multiple Stakeholders
4 June

Shetal Shah, Director of Engineering at Synopsys, explains how to balance divergent expectations across an array of cross-functional stakeholders by focusing on a core solution and enabling customization to meet their specific needs.

Collaboration
Stakeholders
Shetal Shah

Shetal Shah

Director of Engineering at Synopsys

You're a great engineer.
Become a great engineering leader.

Plato (platohq.com) is the world's biggest mentorship platform for engineering managers & product managers. We've curated a community of mentors who are the tech industry's best engineering & product leaders from companies like Facebook, Lyft, Slack, Airbnb, Gusto, and more.