37
votes
Accepted
How do you calculate the compound Service Level Agreement (SLA) for cloud services?
After reading Tensibai's excellent answer, I realised I used to be able to calculate this for network analysis purposes. I dug out my copy of High Availability Network Fundamentals by Chris Oggerino ...
- 11.7k
24
votes
How do you calculate the compound Service Level Agreement (SLA) for cloud services?
I'd take that as a math problem with the SLA being the probability of being OK.
In this case we can rely on probability rules to get an overall.
For your first case the probability that App Service (...
- 11.4k
17
votes
Accepted
What are the pro and cons of SnowFlakes Servers, Phoenix Servers and Immutable Servers?
The term Phoenix Server was coined by a fellow of Martin Fowler, and all three terms described in short articles on Martin's bliki.
Snowflake Server
Phoenix Server
Immutable Server
The pros and cons ...
- 9,003
14
votes
Accepted
Is it ok to have a Jenkins Server without slave node?
https://wiki.jenkins.io/display/JENKINS/Jenkins+Best+Practices
In larger systems, don't build on the master.
If you have a more complex security setup that allows some users to
only ...
- 13.3k
12
votes
Accepted
What is a good logging practice for distributed tasks?
"Serverless" mostly just means you've got relatively simple microservices, generally just a little webapp or a single function that is automatically connected to a REST frontend. The same concepts ...
- 1,197
10
votes
What are the pro and cons of SnowFlakes Servers, Phoenix Servers and Immutable Servers?
As I was more thinking of a listing of advantages and drawbacks of each type, here's is my view (not exhaustive, it's the important operational ones in my opinion):
Snowflakes Servers
What they are: ...
- 11.4k
9
votes
Accepted
Service backend/frontend in one or two containers?
Are they separate projects (from a logical or technical perspective)? Would one ever need to be updated/recreated independently of the other one? Would they need to scale independently of each other? ...
- 3,278
8
votes
Accepted
In ansible how to select specific tasks in a role according to the playbook or a more general parameter?
Different approaches can be useful for different setups. You can use tags in some cases, or conditional includes (as you describe) in other cases.
On the other hand, it generates quite a payload of ...
- 1,123
7
votes
What are DevOps & Ops user stories, or elements in scrum context?
Make sure that your stories are not centered on Operations. Remember that DevOps is a culture not a role. Is an "Operations Engineer" really the stakeholder for the story?
Think of the features and ...
- 2,762
7
votes
How to auto generate a diagram out of my AWS VPC?
Yes and it costs 400$ a month.
https://docs.aws.amazon.com/solutions/latest/aws-perspective/welcome.html
It's a live diagram of all the resource in your organization, which means that it's capable of ...
- 425
6
votes
Accepted
Should I use multiple beats input in Logstash?
So still not benchmarked much, but after a quick code inspection and a bunch of reading about netty and logstash in version 5 the input is not the bottleneck to worry about.
Logstash team did put a ...
- 11.4k
6
votes
What is a good logging practice for distributed tasks?
This answer is more about scalability considerations - if the number of workers can be high and/or multiple of them can produce logs at high rate at the same time.
Yes, using multiple logfiles ...
- 6,750
5
votes
Is it ok to have a Jenkins Server without slave node?
There are some situations where running jobs on the master node is fine, but you do have to be careful. Like the other answer mentioned, generally speaking running jobs on the master is bad practice ...
- 2,992
5
votes
Accepted
How should GCP projects be organized?
Speaking primarily from the Google App Engine (GAE) perspective.
My preference is for environment-driven project split. This might be of interest: Advantages of implementing CI/CD environments at GAE ...
- 6,750
4
votes
How should GCP projects be organized?
Google's recommended best practice is to create an Organisation within GCP so that you get access to folders, then model the hierarchy of your organisation within GCP:
Some guidance/rules:
there ...
- 11.7k
3
votes
Accepted
What are Design Patterns for creating images?
The general design pattern is one container = one running service - see the initial comment at https://docs.docker.com/config/containers/multi-service_container/
Now, after spending about a year ...
- 381
3
votes
Accepted
Limits of a singular Docker Swarm stack
I would say It depend on you preference since redeploying a stack for only 1 or so image, will not restart all the containers present.
In the other hand network feature since docker 17.06 are ...
- 156
3
votes
Accepted
availability calculation of a azure service fabric stateful application
Virtual Machine Scale Sets (VMSSs) don't have a SLA of their own:
Virtual Machine Scale Sets is a free service, therefore, it does not have a financially backed SLA itself. However, if the Virtual ...
- 11.7k
2
votes
What are the pro and cons of SnowFlakes Servers, Phoenix Servers and Immutable Servers?
All three are patterns of sorts, it isn't is a case of picking and choosing which to use in any specific circumstance but a case of knowing when to recognise the patterns that can help or hurt you.
...
- 11.7k
2
votes
How should GCP projects be organized?
We have two projects: production and staging. Later runs dev, qa also. And for billing purpose, we tag resources accordingly.
- 121
2
votes
Service backend/frontend in one or two containers?
We always use different container for each service (Like Frontend ,Backend and Database). Because a container can run only a single service inside it at a time by using docker-compose.yml file. But we ...
- 21
2
votes
Is this an appropriate architecture, or can improvements be made?
My largest concern is around the MS SQL Server implementation. Coupling the read only instances so tightly to the services feels wrong. Is there a better way to do this?
Essentially what you have ...
- 2,841
2
votes
How to add rules to Kubernetes NGINX Ingress controller from different yml definitions?
I was able to combine your two example files by first converting them to JSON.
foo.json
{
"apiVersion": "extensions/v1beta1",
"kind": "Ingress",
"metadata": {
"name": "nginx-ingress"
},
...
- 1,064
2
votes
EC2 EBS Free Tier - Is Storage Reusable?
While I can't find it explicitly written anywhere, I do know that textbooks frequently reference that you can use the free tier to avoid costs, and that they frequently have you create and destroy ...
- 1,550
1
vote
Scale up pods of k8s deployment across spot and dedicated instances
You can follow below approach:
Use Cluster Autoscaler which should scale-in or scale-out nodes as and when required.
Create nodegroups with multiple instance types so that you always get a spot node.
...
- 1,021
1
vote
Provide customers with access to Azure Container Registry
There is a balancing act here between the simplicity and maintainability of your solution, and how auditable creating separate service principals or users for each of your external customers. I ...
- 11.7k
1
vote
Is this an appropriate architecture, or can improvements be made?
I could talk a lot about the architecture yet this is a devops community so I will addresses your main concern about running the database only.
Short answer:
If you were to modify the design to ...
- 1,172
1
vote
How to add rules to Kubernetes NGINX Ingress controller from different yml definitions?
Could I have these two different definitions which creates a single
Ingress with two rules (based on having the same name)?
Lets investigate whether that would be possible.
According to
https://...
- 13.3k
1
vote
Microservices terminology i.e. distinguishing between "core " and "other service instances"
The last couple of years I am/was part of couple of DevOps teams that are/were creating microservices. Some of the projects failed miserably.
Reasons:
architect that only read a blog about ...
- 13.3k
Only top scored, non community-wiki answers of a minimum length are eligible