Master Elasticsearch Snapshots and Security: Step‑by‑Step NFS Backup Guide

1. Official Snapshot Backup and Restore

Configure Elasticsearch nodes to share a common NFS directory for snapshot storage.

Environment Requirements

All Elasticsearch nodes must mount the same shared NFS directory.

<code>yum install nfs-utils -y
# create elasticsearch user and group
groupadd elasticsearch -g 996
useradd elasticsearch -g 996 -u 998 -M -s /sbin/nologin

cat > /etc/exports <<'EOF'
/es-nfs-data 10.0.0.0/24(rw,sync,all_squash,anonuid=998,anongid=996)
EOF
systemctl restart nfs
showmount -e 10.0.0.122</code>

Install NFS Client on ES Nodes

<code>cat > nfs-client.sh <<'EOF'
yum install nfs-utils -y
mkdir -p /es-client-data
mount -t nfs 10.0.0.122:/es-nfs-data /es-client-data
EOF
sh nfs-client.sh
# verify mount
df -h | grep es-client-data</code>

Enable Snapshot on ES Nodes

<code># add to each node's elasticsearch.yml
path.repo: /es-client-data/
cluster.name: yuchao_es
node.name: es-node3
path.data: /var/lib/elasticsearch/
path.logs: /var/log/elasticsearch/
bootstrap.memory_lock: true
network.host: 127.0.0.1,10.0.0.20
http.port: 9200
discovery.seed_hosts: ["10.0.0.18","10.0.0.19","10.0.0.20"]
cluster.initial_master_nodes: ["10.0.0.18"]
</code>

Verify Restart

Restart the Elasticsearch service and ensure it starts without errors.

Register Snapshot Repository

<code>PUT /_snapshot/my_backup
{
  "type": "fs",
  "settings": {"location": "/es-client-data/my_backup_location", "compress": true}
}
GET /_snapshot/my_backup</code>

Create Snapshots

<code># Full snapshot
PUT /_snapshot/my_backup/snapshot_1?wait_for_completion=true

# Snapshot of specific indices
PUT /_snapshot/my_backup/snapshot_2?wait_for_completion=true
{
  "indices": "t1,t2",
  "ignore_unavailable": true,
  "include_global_state": false
}</code>

View Snapshot Information

<code>GET /_snapshot
GET /_snapshot/my_backup/
GET /_snapshot/my_backup/snapshot_1
GET /_snapshot/my_backup/snapshot_2</code>

Restore Data

<code># Delete index t2 then restore it
POST /_snapshot/my_backup/snapshot_2/_restore
{
  "indices": "t2",
  "ignore_unavailable": true,
  "include_global_state": false,
  "rename_pattern": "t(.+)",
  "rename_replacement": "restored_index_$1",
  "include_aliases": false
}</code>

Snapshot Naming with Dates (Not Recommended)

<code>PUT /_snapshot/my_backup/<snapshot-{now/d}>
</code>

2. Third‑Party Backup Tools (elasticdump)

Install Node.js

<code>wget https://nodejs.org/dist/v10.16.3/node-v10.16.3-linux-x64.tar.xz
tar -xf node-v10.16.3-linux-x64.tar.xz
ln -s node-v10.16.3-linux-x64/ node
export PATH=/opt/node/bin:$PATH
npm install elasticdump -g
elasticdump --version</code>

Backup Commands

<code># Export index t1 to JSON
elasticdump \
  --input=http://10.0.0.18:9200/t1 \
  --output=/es-nfs-data/t1.json \
  --type=data

# Export and compress
elasticdump \
  --input=http://10.0.0.18:9200/t2 \
  --output=- | gzip > /es-nfs-data/t2.json.gz</code>

Restore Commands

<code># Import JSON back into Elasticsearch
elasticdump \
  --input=/es-nfs-data/t2.json \
  --output=http://10.0.0.18:9200/t2 \
  --type=data</code>

Batch Backup Script

<code>#!/bin/bash
indexs=$(curl -s 10.0.0.18:9200/_cat/indices | awk '{print $3}' | grep -v '^\.')
for i in $indexs; do
  elasticdump \
    --input=http://10.0.0.18:9200/$i \
    --output=/es-nfs-data/$i.json \
    --type=data
done</code>

Password‑Protected Elasticsearch

<code>elasticdump \
  --input=http://user:[email protected]:9200/t2 \
  --output=/es-nfs-data/t2.json \
  --type=data</code>

3. Elasticsearch Security Configuration

Create Certificates

<code># Generate a CA
/usr/share/elasticsearch/bin/elasticsearch-certutil ca
# Generate node certificates using the CA
/usr/share/elasticsearch/bin/elasticsearch-certutil cert --ca elastic-stack-ca.p12
</code>

Distribute Certificates

<code>scp -r /etc/elasticsearch/certs [email protected]:/etc/elasticsearch/
scp -r /etc/elasticsearch/certs [email protected]:/etc/elasticsearch/</code>

Enable Security in elasticsearch.yml

<code>xpack.security.enabled: true
xpack.security.transport.ssl.enabled: true
xpack.security.transport.ssl.verification_mode: certificate
xpack.security.transport.ssl.keystore.path: certs/elastic-stack-ca.p12
xpack.security.transport.ssl.truststore.path: certs/elastic-stack-ca.p12</code>

Set Built‑in User Passwords

<code>/usr/share/elasticsearch/bin/elasticsearch-setup-passwords interactive</code>

Configure Kibana to Use the New User

<code>elasticsearch.username: "kibana_system"
elasticsearch.password: "123123"
</code>

Create Kibana Space and Role for Limited Access

Define a space (e.g., "dev") and a role that only allows read access to index

t2

, then assign the role to a new user.

<code># Create role
PUT /_security/role/dev_role
{
  "indices": [{"names": ["t2"], "privileges": ["read"]}]
}
# Create user and assign role
POST /_security/user/dev_user
{
  "password": "devpass",
  "roles": ["dev_role"]
}
</code>

Result

The user can log into Kibana, see only the designated space, and access only the allowed index.