Troubleshooting Steps When your Nodes is not accessible¶
Sometimes we may run into troubles when our Virtual Nodes is not accessible, We should be able to identify this problem which is likely causing the issues and fix it ourselves.
In this article, we’ll share you few troubleshooting steps which are the some of the common steps taken by administrators when a node is not accessible, You can refer this steps and fix the issue to get your Server up and accessible.
Verifying the Server Status¶
Before Proceeding to any of the steps, We need to first verify the server status by ping and ssh/rdesktop into your server. If you are able to access your server using the ping and ssh and only your site is not accessible, Then its mostly an issue at the service level and we recommend you to refer this article
What is ping¶
Ping is a computer network administration software utility used to test the reachability of a host on an Internet Protocol network.
You can verify this with the below command
Replace xx.xx.xx.xx with your server IP in the above command.
If you are able to reach the network, You will get similar output to as below
e2e-Vostro-3546:~$ ping 18.104.22.168 PING 22.214.171.124 (126.96.36.199) 56(84) bytes of data. 64 bytes from 188.8.131.52: icmp_seq=1 ttl=52 time=313 ms 64 bytes from 184.108.40.206: icmp_seq=2 ttl=52 time=98.2 ms 64 bytes from 220.127.116.11: icmp_seq=3 ttl=52 time=76.9 ms ^C --- 18.104.22.168 ping statistics --- 3 packets transmitted, 3 received, 0% packet loss, time 2002ms
The above output represents that your server is up and the packet is being transmitted.
When you are unable to reach your network, You will get an output as below where the packet is being not transmitted
e2e-Vostro-3546:~$ ping 22.214.171.124 PING 126.96.36.199 (188.8.131.52) 56(84) bytes of data. ^C --- 184.108.40.206 ping statistics --- 7 packets transmitted, 0 received, 100% packet loss, time 6144ms e2e-Vostro-3546:~$ rtt min/avg/max/mdev = 76.963/162.942/313.633/106.908 ms
From the above command, you can see that there is a packet loss of 100% which indicates that your server is not reachable to the network at all.
If you have disabled ping ICMP on your server, Then you will not be able ping the server even though the server might be up and accessible.
What is SSH¶
The SSH protocol (also referred to as Secure Shell) is a method for secure remote login from one computer to another. If you are using a Linux server, You can SSH to your server and verify whether you are able to access your server. Please refer below command
..Note:: In the above command, replace the username with the actual user of your server and replace xx.xx.xx.xx with your server IP.
What is Rdesktop¶
rdesktop is an implementation of client software for Microsoft’s proprietary Remote Desktop Protocol.rdesktop is an open-source UNIX client for connecting to Windows Remote Desktop. If you are using a windows server, You can check the accessibility of your server using Rdesktop using the below command
rdesktop xx.xx.xx.xx -uusername -ppassword
Replace the username and password with your actual configured username and password
Check The State of Your Node on Myaccount Portal¶
If your node is not accessible and You have verified this using ping and ssh method, Then we need to first check the state of our Node in Myaccount portal and Make sure it’s in Running State. Sometimes Due to High Utilization, Your node could go in Power off state. In such cases, you need to power on your server and take the necessary action to avoid the high utilization of your server.
Reboot Your server¶
If you are not able to log in, chances are that your Node is out of memory or CPU crashed. You would need to reboot the Nodes once from Myaccount Portal and try accessing it.Click on the Reboot button to Restart your virtual compute node. It will take a few minutes to restart your virtual compute node.
Access Console to Troubleshoot¶
- A VNC console is available to provide you direct access to your nodes regardless of your settings.This feature comes to aid in situations such as to log in, revert bad settings, and regain control. Often cases Nodes get out of memory and other Service/Application-level issues where it gets inaccessible. In such cases, you can access the server console and check the exact error and try to resolve it.
- If your node is hanged, The server would get OOM-killer invoked or Show Blank Screen on Console which indicates that the node has been hanged. In this case, we need to reboot the server to resolve the issue and take the necessary action to Increase the resources of the server.
- Other Cases might involved where the Firewalls of the server has been messed up or network configurations of the server have been changed due to which you might Loss public connectivity on your server, In such cases, you need to log in to Console and Revert the Changes which was made.
Once you get access you can reset any misbehaving configuration files or services in order to restore access
Monitor Resources Utilization of Your server¶
- Your Node might get Inaccessible Frequently if you have high resources Utilization on your server. We need to Keep a Constant eye on the Resources of our server to make sure it’s not too highly utilized and Make necessary upgrades of your Nodes when required. The Monitoring of Resources Utilization can be done directly from Myaccount Portal in Monitoring Section or You can use Cloudone Monitoring for detailed analysis.
Check the Disk Utilization¶
Your Node might get inaccessible or even go into Poweroff state when the disk utilization of your server is above 99%, In Such cases, you can log in via console and deletes some Log files or Backup file to clear up some space and get back the server up and accessible. If you are not even able to Login Console, You can contact email@example.com where our Team can help you resolve this issue.
Firewall/ Network Configuration Messed Up¶
In case you made changes in Firewall or Network Configuration or due to certain updated this file has messed and Post which you have lost the Public Connectivity, You can try reverting the changes from the console and If you are not able to rever it back. You have two option - If you have enabled CDP Backup, You would be able to restore the backup of your server - If CDP backup is not activated, You can contact firstname.lastname@example.org where our Team can help you resolve this issue.
Slowness and Network Issues¶
- Check the ping to the server and a standard site like google or Facebook. If you are seeing packet losses in both networks, it could be a local network issue
- If all other sites are working fine (no packet losses on ping) and only your server at e2e is getting packet loss, then it could potentially be a server slowness issue and/or a network issue. In this case, please send us a ping report (your site as well as google.com in parallel) and a traceroute to the server
- If possible, please correlate across multiple network providers. For example, if you have a DSL connection, a second confirmation could be to use the mobile data connection and check
The above is a fairly simple guide to quickly understand where is the issue and use that to quickly get your server up and running. In case the issue is not yet resolved, please contact email@example.com where our Team can help you resolve this issue.