MCS unavailable after securing MapR 7.0 Sandbox container

[rbukarev]

I successfully configured a MapR Sandbox docker container 7.0.0.0_8.1.0_ubuntu18, and then realised it's non-secure. So I went ahead and secured it using this documentation. 

I can connect to it now from another machine using MapR client (e.g. I can run hadoop fs -ls command), but I can't open MCS on that host. Even running netstat -tulpn |grep LISTEN doesn't show that the port 8443 is open. 

How do I troubleshoot it?

[Dave Olker]

Is there a reason you're wanting to test an older release like v7.0 instead of the latest v7.4 version?  I just deployed the latest Docker image in my environment and it creates a secure v7.4 cluster by default:

# wget https://raw.githubusercontent.com/mapr-demos/mapr-db-720-getting-started/main/mapr_devsandbox_container_setup.sh
# chmod +x mapr_devsandbox_container_setup.sh
# ./mapr_devsandbox_container_setup.sh -nwiterface ens192

Wait 10 minutes

# ssh root@localhost -p 2222
root@localhost's password:
Welcome to Ubuntu 20.04.5 LTS (GNU/Linux 3.10.0-1160.99.1.el7.x86_64 x86_64)

* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage

This system has been minimized by removing packages and content that are
not required on a system that users do not log into.

To restore this content, you can run the 'unminimize' command.
Last login: Thu Oct 12 18:54:13 2023 from 172.17.0.1

root@maprdemo:~# maprlogin password
[Password for user 'root' at cluster 'maprdemo.mapr.io': ]
MapR credentials of user 'root' for cluster 'maprdemo.mapr.io' are written to '/tmp/maprticket_0'

root@maprdemo:~# hadoop fs -ls /
Found 4 items
drwxr-xr-x - mapr mapr 5 2023-10-12 18:50 /apps
drwxrwxrwx - mapr mapr 0 2023-10-12 18:49 /tmp
drwxr-xr-x - mapr mapr 1 2023-10-12 18:48 /user
drwxr-xr-x - mapr mapr 1 2023-10-12 18:51 /var

root@maprdemo:~# cat /opt/mapr/conf/mapr-clusters.conf
maprdemo.mapr.io secure=true 172.17.0.2:7222

root@maprdemo:~# cat /opt/mapr/MapRBuildVersion
7.4.0.0.20230728133744.GA

root@maprdemo:~# jps
21509 FsShell
19381 Drillbit
20902 AdminApplication
26470 Gateway
22390 GetJavaProperty
25323 WardenMain
22653 Jps
14541 QuorumPeerMain
27726 CLDB
1566 DataAccessGatewayApplication

[rbukarev]

hi @Dave Olker , yes I tried 7.4 already. The reason I wanted to stick to 7. is because my customer uses it. Troubleshooting this issue would also be a good learning experience, as MapR internals look nightmarishly complex.

[rbukarev · Accepted solution]

So, the issue was that somehow after security had been enabled, the memory consumption grew, and MCS couldn't be started due to lack of memory.

I resized the VM from 8GB to 16GB, and MCS started fine.

[Sunitha_Mod]

Hello @rbukarev,

Awesome! 

We are extremely glad to know you were able to find the solution and we appreciate you for keeping us posted.