The changes align better with recommend best practice according to the number of nodes used in the samples. Depending on your requirements you can use the provided samples as starting points and modifying them to your needs.
deployment.sample.multi1.xmlThis is a sample configuration for a two server deployment with search redundancy.
Removed failover on indexing
The second host has removed <content-distributor> and <indexing-dispatcher> nodes. In a two node system it is better to have a performant system for searching, letting one of the nodes be a pure search server. The configuration still has failover for searching with two search rows.
The number of document processors is increased from 4 to 8
The recommended setup is one document processor per CPU core, and many servers today come with 8 cores (single quad-core cpu with hyper-threading = 8 visible cores in the OS).
The Enterprise Web Crawler has been removed from the configuration
For most scenarios you will use the web crawler in SharePoint instead of the FAST Enterprise Web Crawler, so there is no need to include it in the deployment configuration.
Max-targets for the webanalyzer has been increased from 2 to 4
Max targets specify the number of CPU's the web analyzer utilizes, and aligns better with the number of cpu’s on a typical server.
Removed failover webanalyzer component
By removing the attribute redundant-lookup="true" from the <webanalyzer> node on the first host, and removing the <webanalyzer> node entirely from the second host, failover of the webanalyzer is removed from the sample configuration. In a two server setup failover on this component is not necessary. If the first host which is responsible for indexing dies, indexing will stop working, and the webanalyzer is dependent on indexing in order to get data to work with.
deployment.sample.multi2.xmlThis is a sample configuration for a five server deployment with a separate admin server, search redundancy, feeding redundancy and indexing redundancy. The updated sample has removed redundancy on the web analyzer component.
If a server performing database lookup fails for link analysis, and there is no redundancy, this will block crawling.
Admin server changes
The admin server used to have the Enterprise Web Crawler, but that is now replaced with the web analyzer and 8 document processors.
First indexer node
The web analyzer is moved over to the admin node, and the number of document processors has been increased from 4 to 8.
Second indexer node
Number of document processors increased from 4 to 8, and the failover web analyzer component is removed from the server.
The search node configurations are left as is, only serving search requests.