Solr 4.1: SolrCloud – multiple shards on the same Solr node

Rafał Kuć Solr 0 Comment

We would like to discuss another new feature that will be a part of upcoming Solr 4.1 – the ability to place more than one shard of a given collection on a single Solr instance. As you may know this is not possible currently. So, lets look how this works by comparing Solr 4.1 to 4.0.

In order to illustrate how this feature works I decided to see how the process of creating a new collection looks like. We will use a single Solr instance and our collection with be built of two shards.

Solr 4.0

Solr.xml

What we need to do first is clean the solr.xml file, so it doesn’t have any information about cores. Of course we should do that if we migrate from the earlier Solr version.

Starting Solr

Now we need to run a single Solr instance with embedded ZooKeeper. We do that, by running the following command: 

java -DzkRun -jar start.jar

Preparing configuration

Before creating our collection we need to send all the needed configuration file to ZooKeeper. Assuming that we have Solr installed in /home/solrpl/solr/ directory and that we have our configuration files stored in  /home/solrpl/configs/collection1/conf directory I run the following script that is distributed with Solr 4.0: 

/home/solrpl/solr/cloud-scripts/zkcli.sh -cmd upconfig -zkhost localhost:9983 -confdir /home/solrpl/configs/collection1/conf/ -confname collection1

Creating the collection

We should have our configuration files stored in ZooKeeper so now we can use the collections API to create our collection. In order to do the we run a query to Solr to the /solr/admin/collections endpoint with the action=CREATE parameter that tells Solr that we want to create new collection. We also need to provide the name of the collection by adding the name=collection1 parameter. In addition to that we inform Solr that we want to have our collection divided into two shards (numShard=2) and we don’t want any replicas (replicationFactor=0). So the full request looks like this: 

curl 'http://localhost:8983/solr/admin/collections?action=CREATE&name=collection1&numShards=2&replicationFactor=0'

Solr administration panel view

If you would repeat the above steps and look at the cloud view in Solr administration panel you would see something like this:
Solr 4.0 Cloud View

Comments

As you can see Solr 4.0 didn’t place both shards on a single machine. The shard named shard1 was placed on the xubuntu-virtual node, but the one called shard2 was not assigned. Of course that would change if we had more nodes forming the cluster, but that’s not the point of this entry.

Solr 4.1

Solr.xml

Similar to what we did with Solr 4.0 we start with cleaning the solr.xml file. Of course we should do that if we migrate from the earlier Solr version.

Starting Solr

We do exactly the same when starting Solr 4.1, so we run the following command: 

java -DzkRun -jar start.jar

Preparing configuration

Similar to what we did with Solr 4.0, we need to send our configuration to ZooKeeper. We do that by running exactly the same command as we did before: 

/home/solrpl/solr/cloud-scripts/zkcli.sh -cmd upconfig -zkhost localhost:9983 -confdir /home/solrpl/configs/collection1/conf/ -confname collection1

Collection creation

Creating our collection will be a bit different this time. We send the same values of parameters like action, collection and numShards. However we add a new parameter the maxShardsPerNode one that specifies the maximum number of shards that can be placed on a single Solr instance (by default this value is set to 1). In our case we want to have two shards on a single Solr node so we set this parameter to 2. In addition to that Solr forces us to have at least a single replica, so we need to set the replicationFactor parameter to 1. The whole query looks like this: 

curl 'http://localhost:8983/solr/admin/collections?action=CREATE&name=collection1&numShards=2&replicationFactor=1&maxShardsPerNode=2'

Solr administration panel view

After all the above steps the cloud view in Solr administration panel looks like this:
solr_4.1_cloud

Comments

As you can see, with Solr 4.1 we were able to create collection built of two shards and place both of them on a single Solr node. So if you need to have this kind of functionality you can wait for Solr 4.1 and be sure that it will be working.

Leave a Reply

Your email address will not be published. Required fields are marked *

We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.
Cookies settings
Accept
Privacy & Cookie policy
Privacy & Cookies policy
Cookies list
Cookie name Active

Privacy Policy

What information do we collect?

We collect information from you when you register on our site or place an order. When ordering or registering on our site, as appropriate, you may be asked to enter your: name, e-mail address or mailing address.

What do we use your information for?

Any of the information we collect from you may be used in one of the following ways: To personalize your experience (your information helps us to better respond to your individual needs) To improve our website (we continually strive to improve our website offerings based on the information and feedback we receive from you) To improve customer service (your information helps us to more effectively respond to your customer service requests and support needs) To process transactions Your information, whether public or private, will not be sold, exchanged, transferred, or given to any other company for any reason whatsoever, without your consent, other than for the express purpose of delivering the purchased product or service requested. To administer a contest, promotion, survey or other site feature To send periodic emails The email address you provide for order processing, will only be used to send you information and updates pertaining to your order.

How do we protect your information?

We implement a variety of security measures to maintain the safety of your personal information when you place an order or enter, submit, or access your personal information. We offer the use of a secure server. All supplied sensitive/credit information is transmitted via Secure Socket Layer (SSL) technology and then encrypted into our Payment gateway providers database only to be accessible by those authorized with special access rights to such systems, and are required to?keep the information confidential. After a transaction, your private information (credit cards, social security numbers, financials, etc.) will not be kept on file for more than 60 days.

Do we use cookies?

Yes (Cookies are small files that a site or its service provider transfers to your computers hard drive through your Web browser (if you allow) that enables the sites or service providers systems to recognize your browser and capture and remember certain information We use cookies to help us remember and process the items in your shopping cart, understand and save your preferences for future visits, keep track of advertisements and compile aggregate data about site traffic and site interaction so that we can offer better site experiences and tools in the future. We may contract with third-party service providers to assist us in better understanding our site visitors. These service providers are not permitted to use the information collected on our behalf except to help us conduct and improve our business. If you prefer, you can choose to have your computer warn you each time a cookie is being sent, or you can choose to turn off all cookies via your browser settings. Like most websites, if you turn your cookies off, some of our services may not function properly. However, you can still place orders by contacting customer service. Google Analytics We use Google Analytics on our sites for anonymous reporting of site usage and for advertising on the site. If you would like to opt-out of Google Analytics monitoring your behaviour on our sites please use this link (https://tools.google.com/dlpage/gaoptout/)

Do we disclose any information to outside parties?

We do not sell, trade, or otherwise transfer to outside parties your personally identifiable information. This does not include trusted third parties who assist us in operating our website, conducting our business, or servicing you, so long as those parties agree to keep this information confidential. We may also release your information when we believe release is appropriate to comply with the law, enforce our site policies, or protect ours or others rights, property, or safety. However, non-personally identifiable visitor information may be provided to other parties for marketing, advertising, or other uses.

Registration

The minimum information we need to register you is your name, email address and a password. We will ask you more questions for different services, including sales promotions. Unless we say otherwise, you have to answer all the registration questions. We may also ask some other, voluntary questions during registration for certain services (for example, professional networks) so we can gain a clearer understanding of who you are. This also allows us to personalise services for you. To assist us in our marketing, in addition to the data that you provide to us if you register, we may also obtain data from trusted third parties to help us understand what you might be interested in. This ‘profiling’ information is produced from a variety of sources, including publicly available data (such as the electoral roll) or from sources such as surveys and polls where you have given your permission for your data to be shared. You can choose not to have such data shared with the Guardian from these sources by logging into your account and changing the settings in the privacy section. After you have registered, and with your permission, we may send you emails we think may interest you. Newsletters may be personalised based on what you have been reading on theguardian.com. At any time you can decide not to receive these emails and will be able to ‘unsubscribe’. Logging in using social networking credentials If you log-in to our sites using a Facebook log-in, you are granting permission to Facebook to share your user details with us. This will include your name, email address, date of birth and location which will then be used to form a Guardian identity. You can also use your picture from Facebook as part of your profile. This will also allow us and Facebook to share your, networks, user ID and any other information you choose to share according to your Facebook account settings. If you remove the Guardian app from your Facebook settings, we will no longer have access to this information. If you log-in to our sites using a Google log-in, you grant permission to Google to share your user details with us. This will include your name, email address, date of birth, sex and location which we will then use to form a Guardian identity. You may use your picture from Google as part of your profile. This also allows us to share your networks, user ID and any other information you choose to share according to your Google account settings. If you remove the Guardian from your Google settings, we will no longer have access to this information. If you log-in to our sites using a twitter log-in, we receive your avatar (the small picture that appears next to your tweets) and twitter username.

Children’s Online Privacy Protection Act Compliance

We are in compliance with the requirements of COPPA (Childrens Online Privacy Protection Act), we do not collect any information from anyone under 13 years of age. Our website, products and services are all directed to people who are at least 13 years old or older.

Updating your personal information

We offer a ‘My details’ page (also known as Dashboard), where you can update your personal information at any time, and change your marketing preferences. You can get to this page from most pages on the site – simply click on the ‘My details’ link at the top of the screen when you are signed in.

Online Privacy Policy Only

This online privacy policy applies only to information collected through our website and not to information collected offline.

Your Consent

By using our site, you consent to our privacy policy.

Changes to our Privacy Policy

If we decide to change our privacy policy, we will post those changes on this page.
Save settings
Cookies settings