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 install 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 six variables at the top of the script will need to be modified to suit your environment.

...

#!/bin/sh

TARGET=192.168.10.67
NODEDATA=/usr/local/nmis8/database/nodes
SOURCE_MONGODBLOCATION=/data
SOURCE_MONGODBDIR=mongodb
DESTINATION_MONGODBLOCATION=/var/lib
DESTINATION_MONGODBDIR=mongo
NODES=$(fgrep "'name'" /usr/local/nmis8/conf/Nodes.nmis | awk '{print $3}' | tr "\'" ' ' | tr ',' ' ' | awk '{print $1}')

# copy mongodb
rsync --progress -av $SOURCE_MONGODBLOCATION/$SOURCE_MONGODBDIR $TARGET:$DESTINATION_MONGODBLOCATION/.
ssh $TARGET "chown -R mongod:mongod $DESTINATION_MONGODBLOCATION/$DESTINATION_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

Update your Mongo Config File on the New CentOS 7 Server

Update your /etc/mongod.conf to reflect the current configuration from your old CentOS 6 Server, note that the dbpath could be different from your old environment.  

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.