Purpose

Customers that are running NMIS and OMK applications on CentOS 6 may want to move them to CentOS 7.  Will article will present one method of accomplishing this.

Assumptions

The CentOS 7 server will run the same version of NMIS and OMK applications that are currently running on the CentOS 6 server.

Prerequisites

• Seliunx disabled or configured to allow NMIS/OMK installation.
• Firewall disabled or configured to allow all necessary OMK/NMIS network calls.

Procedure

Prepare Target CentOS 7 Server

Install prerequisite packages

After installing CentOS 7 on the new server install the following packages.

• yum update
• yum install perl
• yum intstall perl-core
• yum install rrdtool
• yum install rrdtool-perl
• yum install libpng12
• yum install rsync
• yum install ntp

Install NMIS and OMK Applications

Install the correct NMIS and OMK application versions on the new CentOS 7 server.  If you no longer have the installer packages for the correct versions contact support@opmantek.com and someone will provide them.

Install SSH Keys

In order for the export script to work a valid ssh key must be installed in the /root/.ssh/authorized_keys file.

Shutdown Related Services

On both the old CentOS 6 and the new CentOS 7 servers shutdown the following services:

• opeventsd
• opconfigd
• opflowd
• omkd
• mongod

Run Export Script

Run the following script on the old CentOS 6 server.  The following four variables at the top of the script will need to be modified to suit your environment.

• TARGET :  IP address of the new CentOS 7 server.
• NODEDATA:  Full path to the directory that contains NMIS node files.
• MONGODBLOC:  Full path to the Mongo database directory.
• MONGODBDIR:  The name of the directory that contains the MongoDB files.

#!/bin/sh

TARGET=192.168.10.67
NODEDATA=/usr/local/nmis8/database/nodes
MONGODBLOC=/var/lib
MONGODBDIR=mongo

NODES=$(fgrep "'name'" /usr/local/nmis8/conf/Nodes.nmis | awk '{print $3}' | tr "\'" ' ' | tr ',' ' ' | awk '{print $1}')

# copy mongodb
rsync --progress -av $MONGODBLOC/$MONGODBDIR $TARGET:$MONGODBLOC/.
ssh $TARGET 'chown -R mongod:mongod $MONGODBLOC/$MONGODBDIR'

for NODE in $NODES
do
 # create a directory to store the node export JSON files.
 install -d $NODEDATA
 
 # export the node records from NMIS
 /usr/local/nmis8/admin/node_admin.pl act=export node=$NODE file=$NODEDATA/$NODE.json
 
 # get the node data to the target server
 rsync -avz -e ssh $NODEDATA/* $TARGET:$NODEDATA/
 rsync -avz -e ssh /usr/local/nmis8/database/nodes/$NODE $TARGET:/usr/local/nmis8/database/nodes
 scp /usr/local/nmis8/var/$NODE* $TARGET:/usr/local/nmis8/var
 
 # remotely add the nodes to the TARGET server
 ssh -t $TARGET "/usr/local/nmis8/admin/node_admin.pl act=create node=$NODE file=$NODEDATA/$NODE.json"

done

# Update the group list with any new groups
ssh -t $TARGET "/usr/local/nmis8/admin/grouplist.pl patch=true"

# copy NMIS/OMK config
rsync --progress -av /usr/local/nmis8/models root@$TARGET:/usr/local/nmis8/.
rsync --progress -av /usr/local/nmis8/conf root@$TARGET:/usr/local/nmis8/.
rsync --progress -av /usr/local/omk/conf root@$TARGET:/usr/local/omk/.

# Fix file permissions
ssh $TARGET /usr/local/nmis8/admin/fixperms.pl

Correct NMIS Hostname on the New CentOS 7 Server

in /usr/local/nmis8/conf put the correct hostname for 'server_name' attribute.

Restart Related Services on the New CentOS 7 Server

Restart the following services:

• mongod
• omkd
• opeventsd
• opconfigd
• opflowd

Verification

Log into the GUI on the new CentOS 7 server and verify each application is functional and presents data from before the migration.