Ambari 2.7 provides UI for API to learn and perform many of the operations. You can launch the UI and play - http://AMBARI-UI:8080/api-docs/ For example: You can delete the Host by simply entering the hostname in the UI. 1. Go to http://AMBARI-HOST:8080/api-docs/#!/Hosts/deleteHost 2. Move to "Delete a host" section 3. Enter the "hostname" 4. click on "Try" . Window popup shows the API response with response (errors) message and code like below. Similar many other Services/Groups/users API can be tried in the same page. This feature makes life easies to find and use the APIs. ... View more

Starting from Ambari 2.7 there are 2 new features to track who did what. 1. In operations history - for every operation there is a user name associated. 2. In Prior versions there is no way to find out who launched Install/Add wizards. Starting from 2.7 there is Username name being shows in the UI. These features make Administrators life easier to track who did what. ... View more

With Ambari 2.6.0 or 2.5.x version if you try to use 2.6.3 ( http://public-repo-1.hortonworks.com/HDP/centos7/2.x/updates/2.6.4.0/HDP-2.6.4.0-91.xml) or 2.6.4 -) http://public-repo-1.hortonworks.com/HDP/centos7/2.x/updates/2.6.3.0/HDP-2.6.3.0-235.xml ) VDF files, it fails to load/parse the files - would see below error in the logs.f "like An internal system exception occurred: Could not load url from http://public-repo-1.hortonworks.com/HDP/centos7/2.x/updates/2.6.4.0/HDP-2.6.4.0-91.xml. null" Those VDF files has GPL tag URLs and these ambari versions can't understand it - hence fails with the above error. You can consider Upgrading the Ambari to 2.6.1 or later versions. If you want to continue using 2.6.0 or earloer Ambari versions then you may have to create private repo and download GPL binaries and work without GPL tags in VDF file. you can contact Hortonworks support for any further help. ... View more

This is applicable for CentOS7/RHEL6 - for CentOS7/RHEL7 please follow https://community.hortonworks.com/articles/188269/javapython-updates-and-ambari-agent-tls-settings.html Upgrading to jdk1.8.0_171 version disables some of the TLSv1_1 TLSv1 protocols and algorithms. With this only option is using TLS1_2 version but CentOS6/RHEL6 uses Python 2.6 and it does not support TLS1_2. Agent-server communication would fail with below error. WARNING 2018-04-24 16:35:10,989 NetUtil.py:124 - Server at https://***.***.***.***:8440 is not reachable, sleeping for 10 seconds...INFO 2018-04-24 16:35:20,990 NetUtil.py:70 - Connecting to https://***.***.***.***:8440/caERROR 2018-04-24 16:35:20,991 NetUtil.py:96 - EOF occurred in violation of protocol (_ssl.c:579)ERROR 2018-04-24 16:35:20,991 NetUtil.py:97 - SSLError: Failed to connect. Please check openssl library versions. To workaround this problem you can tweak /usr/jdk64/jdk1.8.0_112/jre/lib/security/java.security file in Ambari server host to enable some of the algorithms. From: jdk.tls.disabledAlgorithms=SSLv3, RC4, MD5withRSA, DH keySize < 1024, \ EC keySize < 224, DES40_CBC, RC4_40, 3DES_EDE_CBC To: jdk.tls.disabledAlgorithms=SSLv3, RC4, MD5withRSA, DH keySize < 1024, \ EC keySize < 224, DES40_CBC, RC4_40 Please note that this is just a temporary workaround and it is recommended to Upgrade the OS version to use TLS1_2 ... View more

How to increase Read time out value from Ambari stand alone view server to Ambari main server Stand alone Ambari view server makes below call to fetch configurations from Remote server. http://REMOTEAMBARI:8080/api/v1/clusters/CLUSTER_NAME?fields=services/ServiceInfo,hosts,Clusters If this takes more than 10 seconds you will be exception in the logs. because of that non of the views would work. Caused by: java.net.SocketTimeoutException: Read timed out at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.socketRead(SocketInputStream.java:116) at java.net.SocketInputStream.read(SocketInputStream.java:170) at java.net.SocketInputStream.read(SocketInputStream.java:141) at java.io.BufferedInputStream.fill(BufferedInputStream.java:246) at java.io.BufferedInputStream.read1(BufferedInputStream.java:286) at java.io.BufferedInputStream.read(BufferedInputStream.java:345) at sun.net.www.http.HttpClient.parseHTTPHeader(HttpClient.java:704) at sun.net.www.http.HttpClient.parseHTTP(HttpClient.java:647) at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1536) at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1441) at java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:480) at org.apache.ambari.server.controller.internal.URLStreamProvider.processURL(URLStreamProvider.java:218) at org.apache.ambari.server.controller.internal.URLStreamProvider.processURL(URLStreamProvider.java:142) at org.apache.ambari.server.view.RemoteAmbariStreamProvider.readFrom(RemoteAmbariStreamProvider.java:67) at org.apache.ambari.server.view.RemoteAmbariCluster.readFromUrlJSON(RemoteAmbariCluster.java:297) at org.apache.ambari.server.view.RemoteAmbariCluster.access$000(RemoteAmbariCluster.java:51) at org.apache.ambari.server.view.RemoteAmbariCluster$1.load(RemoteAmbariCluster.java:83) at org.apache.ambari.server.view.RemoteAmbariCluster$1.load(RemoteAmbariCluster.java:80) at com.google.common.cache.LocalCache$LoadingValueReference.loadFuture(LocalCache.java:3524) at com.google.common.cache.LocalCache$Segment.loadSync(LocalCache.java:2317) ... 109 more Add the below configuration in Remote/Main Ambari server /etc/ambari-server/conf/ambari.properties file. please note that this needs Ambari-server restart. views.request.read.timeout.millis=20000 Note: This is tried and tested in Ambari-2.5.0.3 version ... View more