Compute
Elastic Cloud Server
Huawei Cloud Flexus
Bare Metal Server
Auto Scaling
Image Management Service
Dedicated Host
FunctionGraph
Cloud Phone Host
Huawei Cloud EulerOS
Networking
Virtual Private Cloud
Elastic IP
Elastic Load Balance
NAT Gateway
Direct Connect
Virtual Private Network
VPC Endpoint
Cloud Connect
Enterprise Router
Enterprise Switch
Global Accelerator
Management & Governance
Cloud Eye
Identity and Access Management
Cloud Trace Service
Resource Formation Service
Tag Management Service
Log Tank Service
Config
OneAccess
Resource Access Manager
Simple Message Notification
Application Performance Management
Application Operations Management
Organizations
Optimization Advisor
IAM Identity Center
Cloud Operations Center
Resource Governance Center
Migration
Server Migration Service
Object Storage Migration Service
Cloud Data Migration
Migration Center
Cloud Ecosystem
KooGallery
Partner Center
User Support
My Account
Billing Center
Cost Center
Resource Center
Enterprise Management
Service Tickets
HUAWEI CLOUD (International) FAQs
ICP Filing
Support Plans
My Credentials
Customer Operation Capabilities
Partner Support Plans
Professional Services
Analytics
MapReduce Service
Data Lake Insight
CloudTable Service
Cloud Search Service
Data Lake Visualization
Data Ingestion Service
GaussDB(DWS)
DataArts Studio
Data Lake Factory
DataArts Lake Formation
IoT
IoT Device Access
Others
Product Pricing Details
System Permissions
Console Quick Start
Common FAQs
Instructions for Associating with a HUAWEI CLOUD Partner
Message Center
Security & Compliance
Security Technologies and Applications
Web Application Firewall
Host Security Service
Cloud Firewall
SecMaster
Anti-DDoS Service
Data Encryption Workshop
Database Security Service
Cloud Bastion Host
Data Security Center
Cloud Certificate Manager
Edge Security
Situation Awareness
Managed Threat Detection
Blockchain
Blockchain Service
Web3 Node Engine Service
Media Services
Media Processing Center
Video On Demand
Live
SparkRTC
MetaStudio
Storage
Object Storage Service
Elastic Volume Service
Cloud Backup and Recovery
Storage Disaster Recovery Service
Scalable File Service Turbo
Scalable File Service
Volume Backup Service
Cloud Server Backup Service
Data Express Service
Dedicated Distributed Storage Service
Containers
Cloud Container Engine
SoftWare Repository for Container
Application Service Mesh
Ubiquitous Cloud Native Service
Cloud Container Instance
Databases
Relational Database Service
Document Database Service
Data Admin Service
Data Replication Service
GeminiDB
GaussDB
Distributed Database Middleware
Database and Application Migration UGO
TaurusDB
Middleware
Distributed Cache Service
API Gateway
Distributed Message Service for Kafka
Distributed Message Service for RabbitMQ
Distributed Message Service for RocketMQ
Cloud Service Engine
Multi-Site High Availability Service
EventGrid
Dedicated Cloud
Dedicated Computing Cluster
Business Applications
Workspace
ROMA Connect
Message & SMS
Domain Name Service
Edge Data Center Management
Meeting
AI
Face Recognition Service
Graph Engine Service
Content Moderation
Image Recognition
Optical Character Recognition
ModelArts
ImageSearch
Conversational Bot Service
Speech Interaction Service
Huawei HiLens
Video Intelligent Analysis Service
Developer Tools
SDK Developer Guide
API Request Signing Guide
Terraform
Koo Command Line Interface
Content Delivery & Edge Computing
Content Delivery Network
Intelligent EdgeFabric
CloudPond
Intelligent EdgeCloud
Solutions
SAP Cloud
High Performance Computing
Developer Services
ServiceStage
CodeArts
CodeArts PerfTest
CodeArts Req
CodeArts Pipeline
CodeArts Build
CodeArts Deploy
CodeArts Artifact
CodeArts TestPlan
CodeArts Check
CodeArts Repo
Cloud Application Engine
MacroVerse aPaaS
KooMessage
KooPhone
KooDrive
Help Center/ Virtual Private Cloud/ FAQs/ Connectivity/ Why Does My ECS Fail to Communicate with Other After It Has Firewall Installed?

Why Does My ECS Fail to Communicate with Other After It Has Firewall Installed?

Updated on 2025-01-17 GMT+08:00

Symptom

An ECS has a single network interface and failed to communicate with others after the ECS has a firewall installed. An example scenario is as follows:

In a VPC, there are three ECSs. Services are deployed on ECS 1 and ECS 2, and a third-party firewall is installed on ECS X. Traffic from ECS 1 and ECS 2 needs to be filtered by the firewall of ECS X.

Fault Locating

The issues here are described in order of how likely they are to occur.

Troubleshoot the issue by ruling out the causes described here, one by one.

Table 1 Fault locating

Possible Cause

Solution

Security group rules

See Whether Security Group Rules Are Configured

Source/destination check

See Whether Source/Destination Check Is Disabled

VPC custom routes

See Whether VPC Custom Routes Are Added

Whether Security Group Rules Are Configured

Subnets in the same VPC can communicate with each other. If your service ECS cannot communicate with the ECS that has firewall installed, check whether they are in the same security group.

If the ECSs are in different security groups, you need to add rules to the security groups to allow access from each other.

For details, see Adding a Security Group Rule.

Whether Source/Destination Check Is Disabled

Check whether the source/destination check function is disabled on the network interface of the ECS with firewall installed. If the function is not disabled, perform the following operations to disable it:

  1. Log in to the management console.
  2. Click in the upper left corner and select the desired region and project.
  3. Click Service List and choose Compute > Elastic Cloud Server.
  4. In the ECS list, click the target ECS name.

    The Summary tab page of the ECS is displayed.

  5. Click the Network Interfaces tab, click to expand information about the primary network interface, and check whether Source/Destination Check is disabled.

    If it is not disabled, disable it.

Whether VPC Custom Routes Are Added

Check whether the subnet route table of the service VPC has a route pointing to the ECS with firewall installed.

If there is no such a route, add a custom route with next hop set to ECS and destination set to the ECS with the firewall installed.

For details, see Adding a Custom Route.

Submitting a Service Ticket

If the problem persists, submit a service ticket.

We use cookies to improve our site and your experience. By continuing to browse our site you accept our cookie policy. Find out more

Feedback

Feedback

Feedback

0/500

Selected Content

Submit selected content with the feedback