i need to replicate 2 Productive Servers on a Backup Server (something like High Availability)
Facts:
3 Servers: 2 Productive (1 Prod_serv: VG has 30TB and 5 LVM's; 2 Prod_Serv - VG has 10TB and 3 LVM; Backup_Serv - 70 TB but no VGs yet. Only OS installed )
the 2 Productive Servers are running Centos 6. Backup_Serv is running Centos 7
All 3 Servers are configured with LVM.
Filesystem: XFS
All Servers are connected with 10G network interfaces.
Q1: What would be the best way to replicate the 2 Productive Servers on the Backup Server?
Q2: Is there any way i could install and configure DRBD on the existing LVM's without having to wipe the data?
Looking forward for your answers!
Related
We have 2 social iOS/Android apps of 100 concurrent users each and we can afford about $500/month in total... Each app should use 1-2 application servers and 1 db server.
I now have 1 application server and 1 db server for each app, both of 4-vcpus and 4GB RAM.
We are currently on Azure, but our 1-year is ending... I'm thinking of Heroku, DigitalOcean, back4app and Syncano. What do you suggest?
if you don't have a lot of users and you don't want to do a lot of work, Heroku is your best option.
However, if you want to have more control over your server, I think using bitnami is a good choice to run your server with a parse server image on your cloud platform of your choice. They support all major clouds.
I am new to Redis & I am in process of setting up a Redis OSS for development region for my project. I have few questions about the deployment model which I want to have validated.
1) Will Redis run on just one node? since my request is for a development region I do not need high availability.
2) Can I create multiple databases to support various projects with one instance I am setting up?
3) I am going with Red Hat Linux since for production I plan to use Redis Enterprise considering its support model.
1) Yes - the redis-server always runs on one node.
2) Yes - you can multiple logical/shared databases on the same server using the SELECT command. That, however, is considered bad practice. You should, instead, use a different redis-server for each database. These redis-server processes CAN be run on the same physical server.
3) You can use the trial version of the Enterprise for development.
Disclaimer: I work for Redis Labs, home of OSS Redis and provider of the Enterprise products line.
Redis proides three development models: single(default),sentinel,cluster. Without considering the model you used, you can just start the redis instance to build a test development.
If you want to support various projects with one instance, you can create a project for one database. Redis supports at most 16 databases. Also, you need do your logical work in Redis for the aimed project with con your destination database.
Redis is a free and opensource software, so it is unnecessary for you to consider if it is an enterprise, unless you buy a customized version from RedisLabs or other software company.
Thanks all ..
On creating multiple databases per http://www.rediscookbook.org/multiple_databases.html its mentioned that we can create multiple databases.
Since this is for development/ test region, I would think creating multiple databases should be fine compared with the production where we would need best performance.
Redis is designed to be single thread which has its own pros and cons. Redis answers for multi core with sharding - https://redis.io/topics/partitioning.
Yes you can create multiple databases in same redis instance though it is not recommended. But since you are setting up staging model its your call.
Hope this helps.
i'm working on an application that needs to be tested in a HPC cluster.
i'm thinking about using xcat as a resource manager.
i don't have much hardware resources, i have one HP desktop and MacBook laptop.
the question: is it possible to set up a virtual cluster (using virtualBox or KVM) on one hardware resource
thanks,
The short answer here is yes, depending on how much memory and disk you have available on your one machine. I've done this numerous times on a MacBook Pro with 8 GB of RAM.
The long answer is that there is absolutely nothing magical about an HPC cluster. All you need to test basic parallel applications in a simulated cluster environment are two or more VMs which meet these criteria:
Same OS, as identical as possible.
Passwordless authentication (ssh key based auth).
Same software stack in same location on all nodes (See #4 or use rsync).
At least one shared filesystem, e.g. NFS mounted $HOME
Shared network with name resolution configured (correct /etc/hosts on all nodes)
None of this requires job schedulers, provisioning tools or any complex networking. You can find many NFS setup howtos to help get one node set up to share $HOME to the others, this might be the most complicated part. VirtualBox does a good job of setting up local networking.
On top of this you can layer setting up a job scheduler like SLURM (highly recommended), provisioning tools like Warewulf or xCat, parallel filesystems across the VMs (BeeGFS is easy to set up and a great introduction), etc. I have had a full featured stateless cluster simulated on my Macbook Pro a number of times using tools from this list and VirtualBox VMs. It's a great way to learn about setting up an HPC cluster.
We have a galera cluster with 3 nodes, on 3 different physical machines but all located in the same datacenter.
From what I understood, the reason they deployed this in the past was to increase availability and reliability.
Each node is installed on a VM using 12 cores and 4Gb RAM.
We are asked to migrate this to Google Cloup Platform in order to get rid of the ops tasks.
I could create 3 compute engine instances and deploy the galera cluster, but I have difficulties to see the added value compared to Cloud SQL instances with replication and backup. I am not very familiar in scaling heavy load systems.
The db hosted in these nodes is kind of critical and should ensure maximum availability and reliability.
What strategy should I adopt in order to migrate this architecture to GCP ?
We have recently purchased the new server having 16 GB of RAM. We have created 5 virtual machine. Out of these 5 virtual machines three are windows VM and the remaining two are Linux VM.
We have been contsantly facing the poor response of the virtual machines and the network / infra team is not able to tell us the root cause of the problem and providing the solution.
Can you please let me know what could be the possible cause of the slow down.
Additionally, we want to have the audits conducted to see if the infrastructure / network for our company has been setup correctly. Can you please let me know what are the typical audit parameters we evalluate for the best performance of Network and SYstems resources.
Thanks for the help.
Memory (RAM) is being distributed among so many VMs, each VM has very less RAM available for its own use.