Created on 11-20-2019 11:41 AM - last edited on 11-20-2019 08:21 PM by ask_bill_brooks
hi all
we are using the following HDP cluster with ambari ,
list of nodes and their RHEL version
3 masters machines ( with namenode & resource manager ) , installed on RHEL 7.2
312 DATA-NODES machines , installed on RHEL 7.2
5 kafka machines , installed on RHEL 7.2
now we want to add the following machines to the cluster but with RHEL 7.5
85 DATA-NODES machines , should be installed on RHEL 7.5 version
2 kafka brokers machines , should be installed on RHEL 7.5 version
so my question is
can we mix in HDP cluster RHEL 7.2 with RHEL 7.5 version ?
Created 11-26-2019 01:25 PM
I thought it was very clear that RHEL 7.7 is not supported as yet by HDP and I doubt whether it will as you well know development has been stopped in that line in prefernce for CDP !!
I didn't mention anywhere to upgrade to 7.7, I tried to correct the typo by trying to elaborate. Your current Cluster OS versions are 7.2 and 7.5 so the best you can do is upgrade all to 7.5 after testing the procedure of course.
On a Linux box if you run the yum update command the yum downloads the latest stable release from the official repo, so to avoid accidentally upgrading to 7.7 which yum update will do you should tell yum what OS version you what by following the steps below or use a satellite server which controls the OS version
Solution to upgrade to 7.5
Execute the following command: subscription-manager release --set=7.5
Clean up everything : sudo yum clean all | sudo rm -r /var/cache/yum
Update the software sources: sudo yum update redhat-release-server
So forget about 7.7 that won't work out and Support matrix shows that , I hope I am now clear 🙂
Created 11-25-2019 08:45 PM
I would say NO from a technical perspective, too many things changed since RHEL 7.2 mixing Family OS's in the same major release RHEL 7.2 and CentOS 7.5 is possible but while less likely, even that could lead to issues as it isn't tested. You'll want to pay close attention to versions of java, yum, python, etc on each node. You might have to edit the /usr/lib/python2.6/site-packages/ambari_server/os_type_check.sh to bypass some incompatibility and you will need to take care of the Kafka conflicts too are they the same versions??
Don't be afraid the fresh installation and configuration takes less time than fixing dependency problems and other issues but the better option is a rolling upgrade to the higher version 7.5
Between RHEL 7.5 and 7.2 you skip two releases not to speak about the jump from GNOME 3.14 to GNOME 3.26, in case the version Server with GUI is in use. Even if (only) upgrading from RHEL 7.2 to RHEL 7.4 - this is something where several problems are possible I think both ways have pros and cons.
Take precautions to avoid accidental updates by using an internal repo like Red Hat Satellite Server for content and configuration management hence protecting any necessary configurations, data, and attempt the yum update. You can do an echo n | yum update to see if it generates any yum errors.
In your case, it would good to upgrade to 7.7 and to avoid getting accidental 7.7 What you can do is to create a local repository that contains the packages from the RHEL 7.5 release and perform an offline upgrade to that edition, but you should disable the network in this case. Otherwise (when you run an online update) yum will pull in the latest stable packages ... which actually are from the current RHEL 7.7 release. 🙂
Solution to upgrade to 7.5
Execute the following command: subscription-manager release --set=7.5
Clean up everything : sudo yum clean all | sudo rm -r /var/cache/yum
Update the software sources: sudo yum update redhat-release-server
On the HDP version, 2.5.x to 3.1.x and Ambari 2.5.x to 2.7.x can run without issues on RHEL 7.2 but RHEL 7.5 can only run HDP 2.6.0 to 2.1.4 and Ambari 2.6.2 to 2.7.4
Created 11-26-2019 10:25 AM
hi Shelton
you mention to upgrade to version 7.7
but https://supportmatrix.hortonworks.com/ , when you click on 7.7 , we not see any selected HDP or ambari
so I gues you means to upgrade to 7.6 version ( because 7.7 not approved for any HDP )
Created on 11-26-2019 11:16 AM - edited 11-26-2019 11:18 AM
it was a typo error I should have proofread again
"In your case, it would good to upgrade to 7.7 and to avoid getting accidental 7.7" should read In your case, it would good to upgrade to 7.5 and to avoid getting accidental 7.7 this should match the highest version in your cluster else when you run system update this will automatically upgrade to the latest stable version 7.7 that why you should use the internal repo or set subscription-manager release --set=7.5
NB. Upgrading to 7.6 as you said would mean a lot of upgrade work for both clusters
Happy hadooping
Created 11-26-2019 12:46 PM
so lets summary to avoid mistake
rhel 7.7 can support HDP 2.6.4 and up ( latet HDP version )
rhel 7.7 can support 2.6.2.2 , 2.7.3 , 2.7.4 ambari version
is it correct until now?
second
when current rhel version is 7.2 and we want to add rhel 7.7 OS version
then its fully recommended to upgrade 7.2 to 7.7
is it correct ?
Created 11-26-2019 01:25 PM
I thought it was very clear that RHEL 7.7 is not supported as yet by HDP and I doubt whether it will as you well know development has been stopped in that line in prefernce for CDP !!
I didn't mention anywhere to upgrade to 7.7, I tried to correct the typo by trying to elaborate. Your current Cluster OS versions are 7.2 and 7.5 so the best you can do is upgrade all to 7.5 after testing the procedure of course.
On a Linux box if you run the yum update command the yum downloads the latest stable release from the official repo, so to avoid accidentally upgrading to 7.7 which yum update will do you should tell yum what OS version you what by following the steps below or use a satellite server which controls the OS version
Solution to upgrade to 7.5
Execute the following command: subscription-manager release --set=7.5
Clean up everything : sudo yum clean all | sudo rm -r /var/cache/yum
Update the software sources: sudo yum update redhat-release-server
So forget about 7.7 that won't work out and Support matrix shows that , I hope I am now clear 🙂
Created on 11-26-2019 02:09 PM - edited 11-26-2019 02:16 PM
ok
so after second thinking I think its better to use the latest version that supported - 7.6 instead of 7.5
rhel 7.6 can support HDP 2.6.4 and up ( latest HDP version )
rhel 7.6 can support 2.6.2.2 , 2.7.3 , 2.7.4 ambari version
and
when current rhel version is 7.2 and we want to add rhel 7.6 OS version
then its fully recommended to upgrade 7.2 to 7.6