I have a weblogic 12 cluster. Files get pushed to it both through http forms and through scp to a single machine on the cluster. However I need the files on all the nodes of the cluster. I can run scp myself and copy to all parts of the cluster, but I was hoping that weblogic supported the functionality in some manner. I don't have a disk shared between the machines that would make this easier. Nor can I create a shared disk.
Does anybody know?
No There is no way for WLS to ensure a file copied on one instance of WLS is copied to another. Especially when you are copying it over even using scp.
Please use a shared storage mount, so that all managed servers can refer to this location with out the need to do SCP.
Related
I am a newbie of GKE. I created a GKE cluster with very simple setup. It only has on gpu node and all other stuff was default. After the cluster is up, I was able to list the nodes and ssh into the nodes. But I have two questions here.
I tried to install nvidia driver using the command:
kubectl apply -f https://raw.githubusercontent.com/GoogleCloudPlatform/container-engine-accelerators/master/nvidia-driver-installer/cos/daemonset-preloaded.yaml
It output that:
kubectl apply --filename https://raw.githubusercontent.com/GoogleCloudPlatform/container-engine-accelerators/master/nvidia-driver-installer/cos/daemonset-preloaded.yaml
daemonset.apps/nvidia-driver-installer configured
But 'nvidia-smi' cannot be found at all. Should I do something else to make it work?
On the worker node, there wasn't the .kube directory and the file 'config'. I had to copy it from the master node to the worker node to make things work. And the config file on the master node automatically updates so I have to copy again and again. Did I miss some steps in the creation of the cluster or how to resolve this problem?
I appreciate someone can shed some light on this. It drove me crazy after working on it for several days.
Tons of thanks.
Alex.
For the DaemonSet to work, you need to have a tag on your worker Node as cloud.google.com/gke-accelerator (see this line). The DaemonSet checks for this tag on a node before scheduling any pods for installing the driver. I'm guessing a default node pool you create did not have this tag on it. You can find more details on this on the GKE docs here.
The worker nodes, by design are just that worker nodes. They do not need privileged access to the Kubernetes API so they don't need any kubeconfig files. The communication between worker nodes and the API is strictly controlled through the kubelet binary running on the node. Therefore, you will never find kubeconfig files on a worker node. Also, you should never put them on the worker node either, since if a node gets compromised, the keys in that file can be used to damage the API Server. Instead, you should make it a habit to either use the master nodes for kubectl commands, or better yet, have the kubeconfig on your local machine, and keep it safe, and issue commands remotely to your cluster.
After all, all you need is access to an API endpoint for your Kubernetes API server, and it shouldn't matter where you access it from, as long as the endpoint is reachable. So, there is no need whatsoever to have kubeconfig on the worker nodes :)
I want to make sure I'm not storing sensitive keys and credentials in source or in docker images. Specifically I'd like to store my MySQL RDS application credentials and copy them when the container/task starts. The documentation provides an example of retrieving the ecs.config file from s3 and I'd like to do something similar.
I'm using the Amazon ECS optimized AMI with an auto scaling group that registers with my ECS cluster. I'm using the ghost docker image without any customization. Is there a way to configure what I'm trying to do?
You can define a volume on the host and map it to the container with Read only privileges.
Please refer to the following documentation for configuring ECS volume for an ECS task.
http://docs.aws.amazon.com/AmazonECS/latest/developerguide/using_data_volumes.html
Even though the container does not have the config at build time, it will read the configs as if they are available in its own file system.
There are many ways to secure the config on the host OS.
In my past projects, I have achieved the same by disabling ssh into the host and injecting the config at boot-up using cloud-init.
I'm trying to architect a system on GCP for scalable web/app servers. My initial intention was to have one disk per web server group hosting the OS, and another hosting the source code + imagery etc. My idea was to mount the OS disk on multiple VM instances so to have exact clones of the servers, with one place to store PHP session files (so moving in between different servers would be transparent and not cause problems).
The second idea was to mount a 2nd disk, containing the source code and media files, which would then be shared with 2 web servers, one configured as a CDN server and one with the main website and backend. The backend would modify/add/delete media files, and the CDN server would supply them to the browser when requested.
My problem arises when reading that the Persistent Disk Storage is only mountable on a single VM instance with read/write access, and if it's needed on multiple instances it can be mounted only in write access. I need to have one of the instances with read/write access with the others (possibly many) with read only access.
Would you be able to suggest ways or methods on how to implement such a system on the GCP, or if it's not possible at all?
Unfortunately, it's not possible.
But, you can create a Single-Node File Server and mount it as a read and write disk on other VMs.
GCP has documentation on how to create a single-Node File Server
An alternative to using persistent (which as you said, only alows a single RW mount or many read-only) is to use Cloud Storage - which can be mounted through FUSE.
We have a site where users upload files, some of them quite large. We've got multiple EC2 instances and would like to load balance them. Currently, we store the files on an EBS volume for fast access. What's the best way to replicate the files so they can be available on more than one instance?
My thought is that some automatic replication process that uploads the files to S3, and then automatically downloads them to other EC2 instances would be ideal.
EBS snapshots won't work because they replicate the entire volume, and we need to be able to replicate the directories of individual customers on demand.
You could write a shell script that would spawn s3cmd to sync your local filesystem with a S3 bucket whenever a new file is uploaded (or deleted). It would look something like:
s3cmd sync ./ s3://your-bucket/
Depends on what OS you are running on your EC2 instances:
There isn't really any need to add S3 to the mix unless you want to store them there for some other reason (like backup).
If you are running *nix the classic choice might be to run rsync and just sync between instances.
On Windows you could still use rsync or else SyncToy from Microsoft is a simple free option. Otherwise there are probably hundreds of commercial applications in this space...
If you do want to sync to S3 then I would suggest one of the S3 client apps like CloudBerry or JungleDisk, which both have sync functionality...
If you are running Windows it's also worth considering DFS (Distributed File System) which provides replication and is part of Windows Server...
The best way is to use the Amazon Cloud Front service. All of the replication is managed as part of the AWS. Content is served from several different availability zones, but does not require you to have EBS volumes in those zones.
Amazon CloudFront delivers your static and streaming content using a global network of edge locations. Requests for your objects are automatically routed to the nearest edge location, so content is delivered with the best possible performance.
http://aws.amazon.com/cloudfront/
Two ways:
Forget EBS, transfer the files to S3 and use S3 as your file-manager than EBS, add cloudfront and use the common-link everywhere.
Mount S3 bucket on any machines.
1. Amazon CloudFront is a web service for content delivery. It delivers your static and streaming content using a global network of edge locations.
http://aws.amazon.com/cloudfront/
2. You can mount S3 bucket on your linux machine. See below:
s3fs -
http://code.google.com/p/s3fs/wiki/InstallationNotes
- this did work for me. It uses FUSE file-system + rsync to sync the files
in S3. It kepes a copy of all
filenames in the local system & make
it look like a FILE/FOLDER.
That way you can share the S3 bucket on different machines.
If I have two directories on an nfs server, between which I would like to copy a large amount of data (in several thousand files, rather than one large block), is there any way to optimize this to be a "local" copy on the server? Does NFS do this automatically, and if not, is there an option to enable it to do so, or is there some inevitable hit on the client? sshing into the nfs server is not an option, sadly - the nfs mount is the only access I have to it.
No, NFS doesn't do this, unfortunately. There is no provision in the protocol for the source of the copy to know anything about the destination or vice versa.
Without ssh or similar access, you can't do anything other than drag every byte across the network to the client, and send it back across the network to the server, a block at a time.
You might get some speed-up if you can use tar or dd or some other command where you can modify the block size. But I wouldn't bet on it.