Azure虚拟机上CDH Manager Web门户无法访问问题排查求助

Let’s work through this step by step—since you already configured the Azure NSG, the issue is likely on the VM itself or a subtle NSG misconfiguration. Here's what to check:

1. Verify CDH Manager Service is Running First #

If the service isn’t up, nothing will listen on 7180. Log into your RHEL VM via SSH and run:

systemctl status cloudera-scm-server

If it shows inactive or failed, start it with:

systemctl start cloudera-scm-server

For startup failures, debug using the service logs:

tail -f /var/log/cloudera-scm-server/cloudera-scm-server.log

Common culprits here are database connection issues (CDH uses PostgreSQL by default) or missing system dependencies.

2. Check VM Internal Firewall (firewalld/iptables) #

Azure NSG rules are great, but RHEL’s local firewall might still block the port.

For firewalld (default on newer RHEL): #

Check if 7180 is allowed:

firewall-cmd --list-all

If 7180/tcp doesn’t appear in the ports section, add it permanently:

firewall-cmd --add-port=7180/tcp --permanent
firewall-cmd --reload

For iptables (older RHEL versions): #

List current rules:

iptables -L

Add an accept rule for 7180:

iptables -A INPUT -p tcp --dport 7180 -j ACCEPT
service iptables save

3. Confirm CDH Manager is Binding to All Network Interfaces #

Sometimes CDH Manager only listens on localhost (127.0.0.1), which blocks external connections. Check which IP the service is bound to:

ss -tulpn | grep 7180

If the output shows 127.0.0.1:7180 instead of 0.0.0.0:7180, update the CDH config:

1. Edit the default config file:

   vi /etc/default/cloudera-scm-server
   

2. Add or modify this line (replace <VM_PUBLIC_IP> with your VM’s public IP, or private IP if accessing from the Azure VNet):

   CMF_JAVA_OPTS="-Djava.rmi.server.hostname=<VM_PUBLIC_IP> -Dcom.sun.management.jmxremote.host=<VM_PUBLIC_IP>"
   

3. Restart the service:

   systemctl restart cloudera-scm-server
   

   Recheck the listening port with the ss command—it should now show 0.0.0.0:7180.

4. Double-Check Azure NSG Configuration Details #

Even if you added a rule, small mistakes can break it:

• Ensure the rule is Inbound (not Outbound).
• Protocol is set to TCP (CDH Manager uses TCP for 7180).
• Source is 0.0.0.0/0 (any origin) or your specific IP range.
• Priority is set lower than default deny rules (e.g., 100–999—lower numbers mean higher priority).
• Confirm the NSG is attached to your VM’s subnet or the VM itself (NSGs don’t work if unlinked to the right resource).
• Make sure you’re accessing the VM’s public IP address (not private IP) unless you’re on the same Azure VNet.

5. Check SELinux Enforcement #

SELinux can block network traffic even if firewalls are open. Check its status:

getenforce

If it returns Enforcing, temporarily disable it to test:

setenforce 0

Try accessing 7180 again. If it works, choose one of these permanent fixes:

• Set SELinux to permissive: Edit /etc/selinux/config and change SELINUX=enforcing to SELINUX=permissive, then reboot.
• Or allow port 7180 through SELinux (more secure):

  semanage port -a -t http_port_t -p tcp 7180
  

Go through these steps one by one—most of the time, the issue is either the local firewall, a stopped service, or CDH binding to localhost.

内容的提问来源于stack exchange，提问作者Vignesh