There are some large datasets (25gb+, downloadable on the Internet) that I want to play around with using Amazon EMR. Instead of downloading the datasets onto my own computer, and then re-uploading them onto Amazon, what's the best way to get the datasets onto Amazon?
Do I fire up an EC2 instance, download the datasets (using wget) into S3 from within the instance, and then access S3 when I run my EMR jobs? (I haven't used Amazon's cloud infrastructure before, so not sure if what I just said makes any sense.)
I recommend the following...
fire up your EMR cluster
elastic-mapreduce --create --alive --other-options-here
log on to the master node and download the data from there
wget http://blah/data
copy into HDFS
hadoop fs -copyFromLocal data /data
There's no real reason to put the original dataset through S3. If you want to keep the results you can move them into S3 before shutting down your cluster.
If the dataset is represented by multiple files you can use the cluster to download it in parallel across the machines. Let me know if this is the case and I'll walk you through it.
Mat
If you're just getting started and experimenting with EMR, I'm guessing you want these on s3 so you don't have to start an interactive Hadoop session (and instead use the EMR wizards via the AWS console).
The best way would be to start a micro instance in the same region as your S3 bucket, download to that machine using wget and then use something like s3cmd (which you'll probably need to install on the instance). On Ubuntu:
wget http://example.com/mydataset dataset
sudo apt-get install s3cmd
s3cmd --configure
s3cmd put dataset s3://mybucket/
The reason you'll want your instance and s3 bucket in the same region is to avoid extra data transfer charges. Although you'll be charged in bound bandwidth to the instance for the wget, the xfer to S3 will be free.
I'm not sure about it, but to me it seems like hadoop should be able to download files directly from your sources.
just enter http://blah/data as your input, and hadoop should do the rest. It certainly works with s3, why should it not work with http?
Related
I want to backup the REDIS data on google storage bucket as flat file, is there any existing utility to do that?
Although, I do not fully agree to idea of backing up of cache data on cloud. I was wondering if there is any existing utility rather than reinventing the wheel.
If you are using Cloud Memorystore for Redis you can simply refer to the following documentation. Notice that you can simply use the following gcloud command:
gcloud redis instances export gs://[BUCKET_NAME]/[FILE_NAME].rdb [INSTANCE_ID] --region=[REGION] --project=[PROJECT_ID]
or use the Export operation from the Cloud Console.
If you manage your own instance (e.g. you have the Redis instance hosted on a Compute Engine Instance) you could simply use the SAVE or BGSAVE (preferred) commands to take a snapshot of the instance and then upload the .rdb file to Google Cloud Storage using any of the available methods, from which I think the most convenient one would be gsutil (notice that it will require the following installation procedure) in a similar fashion to:
gsutil cp path/to/your-file.rdb gs://[DESTINATION_BUCKET_NAME]/
I am currently using RIAK CS as an S3 Provider but I want to change to Scality S3. Therefore, I need to migrate the existing data from RIAK to Scality. Is there a quick an easy way of syncing buckets between the two different storage providers? I have got two docker containers running containing the docker images for the two.
One way of doing it would be to simply download the contents of the buckets to a local folder and then upload to Scality using s3cmd or a similar tool. However, I was hoping there was a direct route between the buckets.
Any ideas?
There would not be a "direct route between the buckets".
While the Amazon S3 CopyObject command can copy objects between different Amazon S3 buckets (even if they are in different regions), it will not work with a non-Amazon endpoint.
Your only hope is if Riak/Scality have somehow built-in connectivity with each other.
i am a little puzzled i hope someone can help me out.
we create some ORC-Files that we would like to query while they are stored on S3.
We noticed that the S3 native Filesystem S3n does not really work out for this manner. I am not really sure what the problem is - but my guess is, that the reader is not able to jump to specific bytes inside the file so that he has to load the whole file before he can query it.
So we tried storing the files on S3 (uri s3://) which is a block file system just like HDFS backed by s3 and it worked great.
But i am a little worried after reading up on this source about Amazon EMR which says
Amazon S3 block file system (URI path: s3bfs://)
The Amazon S3 block file system is a legacy file storage system. We strongly discourage the use of this system.
Important
We recommend that you do not use this file system because it can trigger a race condition that might cause your cluster to fail. However, it might be required by legacy applications.
EMRFS (URI path: s3://)
EMRFS is an implementation of HDFS used for reading and writing regular files from Amazon EMR directly to Amazon S3.
I am not using EMR - i create my files by launching an EC2 cluster and then use s3 as a cold storage - but I am kind of puzzled right now and not sure which filesystem I use when I store my files on s3 using the URI scheme s3:// - do i use EMRFS or do i use the deprecated s3bfs filesystem?
Amazon S3 is an object storage system. It is not recommended to "mount" S3 as a filesystem. Amazon Elastic Block Store (EBS) is a block storage system that appears as volumes on Amazon EC2 instances.
When used from Amazon Elastic MapReduce (EMR), Hadoop has extensions that make it easy to work with Amazon S3. However, if you are not using EMR, there is no need to use EMRFS (which is available only on EMR), nor should you use S3 as a block storage system.
The easiest way to use S3 from EC2 is via the AWS Command-Line Interface (CLI). You can copy files to/from S3 by using the aws s3 cp command. There's also a sync command to make it easy to syncrhonize data to/from S3.
You can also programmatically connect to Amazon S3 via an SDK, so that your app can directly transfer files to/from S3.
As to which to choose... typically, applications like to work with files on a local filesystem, so copy your files from S3 to a local device. However, if your app can directly communicate with S3, there will be less "moving parts".
I'm running hive over EMR,
and need to copy some files to all EMR instances.
One way as I understand is just to copy files to the local file system on each node the other is to copy the files to the HDFS however I haven't found a simple way to copy stright from S3 to HDFS.
What is the best way to go about this?
the best way to do this is to use Hadoop's distcp command. Example (on one of the cluster nodes):
% ${HADOOP_HOME}/bin/hadoop distcp s3n://mybucket/myfile /root/myfile
This would copy a file called myfile from an S3 bucket named mybucket to /root/myfile in HDFS. Note that this example assumes you are using the S3 file system in "native" mode; this means that Hadoop sees each object in S3 as a file. If you use S3 in block mode instead, you would replace s3n with s3 in the example above. For more info about the differences between native S3 and block mode, as well as an elaboration on the example above, see http://wiki.apache.org/hadoop/AmazonS3.
I found that distcp is a very powerful tool. In addition to being able to use it to copy a large amount of files in and out of S3, you can also perform fast cluster-to-cluster copies with large data sets. Instead of pushing all the data through a single node, distcp uses multiple nodes in parallel to perform the transfer. This makes distcp considerably faster when transferring large amounts of data, compared to the alternative of copying everything to the local file system as an intermediary.
Now Amazon itself has a wrapper implemented over distcp, namely : s3distcp .
S3DistCp is an extension of DistCp that is optimized to work with
Amazon Web Services (AWS), particularly Amazon Simple Storage Service
(Amazon S3). You use S3DistCp by adding it as a step in a job flow.
Using S3DistCp, you can efficiently copy large amounts of data from
Amazon S3 into HDFS where it can be processed by subsequent steps in
your Amazon Elastic MapReduce (Amazon EMR) job flow. You can also use
S3DistCp to copy data between Amazon S3 buckets or from HDFS to Amazon
S3
Example Copy log files from Amazon S3 to HDFS
This following example illustrates how to copy log files stored in an Amazon S3 bucket into HDFS. In this example the --srcPattern option is used to limit the data copied to the daemon logs.
elastic-mapreduce --jobflow j-3GY8JC4179IOJ --jar \
s3://us-east-1.elasticmapreduce/libs/s3distcp/1.latest/s3distcp.jar \
--args '--src,s3://myawsbucket/logs/j-3GY8JC4179IOJ/node/,\
--dest,hdfs:///output,\
--srcPattern,.*daemons.*-hadoop-.*'
Note that according to Amazon, at http://docs.amazonwebservices.com/ElasticMapReduce/latest/DeveloperGuide/FileSystemConfig.html "Amazon Elastic MapReduce - File System Configuration", the S3 Block FileSystem is deprecated and its URI prefix is now s3bfs:// and they specifically discourage using it since "it can trigger a race condition that might cause your job flow to fail".
According to the same page, HDFS is now 'first-class' file system under S3 although it is ephemeral (goes away when the Hadoop jobs ends).
I have a fairly large amount of data (~30G, split into ~100 files) I'd like to transfer between S3 and EC2: when I fire up the EC2 instances I'd like to copy the data from S3 to EC2 local disks as quickly as I can, and when I'm done processing I'd like to copy the results back to S3.
I'm looking for a tool that'll do a fast / parallel copy of the data back and forth. I have several scripts hacked up, including one that does a decent job, so I'm not looking for pointers to basic libraries; I'm looking for something fast and reliable.
Unfortunately, Adam's suggestion won't work as his understanding of EBS is wrong (although I wish he was right and often thought myself it should work that way)... as EBS has nothing to do with S3, but it will only give you an "external drive" for EC2 instances that are separate, but connectable to the instances. You still have to do copying between S3 and EC2, even though there are no data transfer costs between the two.
You didn't mention an operating system of your instance, so I cannot give tailored information. A popular command line tool I use is http://s3tools.org/s3cmd ... it is based on Python and therefore, according to info on its website it should work on Win as well as Linux, although I use it ALL the time on Linux. You could easily whip up a quick script that uses its built in "sync" command that works similar to rsync, and have it triggered every time you're done processing your data. You could also use the recursive put and get commands to get and put data only when needed.
There are graphical tools like Cloudberry Pro that have some command line options for Windows too that you can setup schedule commands. http://s3tools.org/s3cmd is probably the easiest.
By now, there is a sync command in the AWS Command line tools, that should do the trick: http://docs.aws.amazon.com/cli/latest/reference/s3/sync.html
On startup:
aws s3 sync s3://mybucket /mylocalfolder
before shutdown:
aws s3 sync /mylocalfolder s3://mybucket
Of course, the details are always fun to work out eg. how can parallel it is (and can you make it more parallel and is that any faster goven the virtual nature of the whole setup)
Btw hope you're still working on this... or somebody is. ;)
I think you might be better off using an Elastic Block Store to store your files instead of S3. An EBS is akin to a 'drive' on S3 that can be mounted into your EC2 instance without having to copy the data each time, thereby allowing you to persist your data between EC2 instances without having to write to or read from S3 each time.
http://aws.amazon.com/ebs/
Install s3cmd Package as
yum install s3cmd
or
sudo apt-get install s3cmd
depending on your OS
then copy data with this
s3cmd get s3://tecadmin/file.txt
also ls can list the files.
for more detils see this
For me the best form is:
wget http://s3.amazonaws.com/my_bucket/my_folder/my_file.ext
from PuTTy