How to Set Up Real‑Time NFS Static Asset Backup with inotify and rsync

1. Install and configure rsync daemon on the backup server

On rsync-test-241 install rsync, then edit /etc/rsyncd.conf with the following key parameters:

uid/gid : run the daemon as the rsync user.

use chroot = no : disable chroot for simplicity.

max connections = 200 : allow up to 200 concurrent connections.

log file = /var/log/rsyncd.log : log activity.

hosts allow = 172.16.1.0/24 : whitelist the internal network.

auth users = rsync_backup and secrets file = /etc/rsync.password : enable password‑based authentication.

[backup-nfs] module with path = /backup/ and read only = false.

# yum install rsync -y
# vim /etc/rsyncd.conf   # (add the configuration above)
# systemctl start rsyncd
# systemctl enable rsyncd

2. Create the rsync user and authentication files

# useradd rsync -s /sbin/nologin -M
# echo "rsync_backup:mima666" > /etc/rsync.password
# chmod 600 /etc/rsync.password
# mkdir /backup
# chown -R rsync.rsync /backup

3. Verify the rsync service

# systemctl status rsyncd
# netstat -tnlp | grep rsync   # should show listening on port 873

4. Install rsync on the NFS source server and perform a test sync

# yum install rsync -y
# rsync -avzP network_init.sh [email protected]::backup-nfs --password-file=/etc/rsync.password

The options mean: -a: preserve file attributes. -v: verbose output. -z: compress data during transfer. -P: show progress.

5. Deploy inotify‑tools on the NFS server to trigger real‑time sync

# yum install inotify-tools -y

Create rsync_nginx.sh:

#!/bin/bash
/usr/bin/inotifywait -mrq -e modify,delete,create,attrib,move /nfs-web-share/ |
while read line; do
    rsync -a --delete /nfs-web-share/ [email protected]::backup-nfs --password-file=/etc/rsync.password
    echo "$(date +%F\ %T) 事件 $line" >> /var/log/rsync.log 2>&1
done

Run the script in the background:

# bash rsync_nginx.sh &

6. Validate the end‑to‑end synchronization

Modify a file on web-test-207 (e.g., index.html) and then check:

Log on nfs-test-231 ( tail -f /var/log/rsync.log) shows the inotify event.

On rsync-test-241 the file appears under /backup with the same content.

7. Common troubleshooting

If synchronization fails, verify:

Firewalls are disabled or ports opened (TCP 873).

NFS export permissions allow the client.

Network connectivity between the three hosts.