Steps When Your Node is Not Accessible
Sometimes we may run into troubles when our Virtual Nodes are not accessible. We should be able to identify the problem that is likely causing the issues and fix it ourselves.
In this article, we’ll share a few troubleshooting steps that are commonly taken by administrators when a node is not accessible. You can refer to these steps and fix the issue to get your server up and accessible.
Verifying the Server Status
Before proceeding with any of the steps, we need to first verify the server status by pinging and SSH/rdesktop into your server. If you are able to access your server using ping and SSH, and only your site is not accessible, then it's mostly an issue at the service level. We recommend you refer to 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:
ping xx.xx.xx.xx
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 164.52.200.65
PING 164.52.200.65 (164.52.200.65) 56(84) bytes of data.
64 bytes from 164.52.200.65: icmp_seq=1 ttl=52 time=313 ms
64 bytes from 164.52.200.65: icmp_seq=2 ttl=52 time=98.2 ms
64 bytes from 164.52.200.65: icmp_seq=3 ttl=52 time=76.9 ms
^C
--- 164.52.200.65 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 164.52.200.65
PING 164.52.200.65 (164.52.200.65) 56(84) bytes of data.
^C
--- 164.52.200.65 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
ssh username@xx.xx.xx.xx
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 <https://myaccount.e2enetworks.com/>_ 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 the CPU has crashed. You would need to reboot the node once from the 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
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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, nodes get out of memory or face other service/application-level issues where they become inaccessible. In such cases, you can access the server console, check the exact error, and try to resolve it.
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If your node is hung, the server would get the OOM-killer invoked or show a blank screen on the console, indicating that the node has been hanged. In this case, you need to reboot the server to resolve the issue and take the necessary action to increase the resources of the server.
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Other cases might involve issues like the firewalls of the server being misconfigured or the network settings being altered, causing you to lose public connectivity on your server. In such cases, you need to log in to the console and revert the changes made.
Once you get access, you can reset any misbehaving configuration files or services to restore access.
Monitor Resources Utilization of Your Server
Your node might become inaccessible frequently if you have high resource utilization on your server. We need to keep a constant eye on the resources of our server to make sure it’s not highly utilized and make necessary upgrades when required. Monitoring resource utilization can be done directly from the MyAccount portal in the Monitoring section, or you can use CloudOne Monitoring for detailed analysis.
Check the Disk Utilization
Your node might become inaccessible or even go into the power-off state when the disk utilization of your server exceeds 99%. In such cases, you can log in via the console and delete some log files or backup files to clear up some space and get the server back up and accessible. If you are unable to log in to the console, you can contact cloud-platform@e2enetworks.com, and our team can assist you in resolving the issue.
Firewall/Network Configuration Messed Up
In case you made changes to the firewall or network configuration, or if certain updates have messed up these files and you have lost public connectivity, you can try reverting the changes from the console. If you are unable to revert them, you have two options:
- If you have enabled CDP Backup, you can restore the backup of your server.
- If CDP backup is not activated, you can contact cloud-platform@e2enetworks.com, and our team will help you resolve the issue.
Slowness and Network Issues
- Check the ping to the server and a standard site like Google or Facebook. If you see 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 experiencing packet loss, then it could 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 check across multiple network providers. For example, if you have a DSL connection, a second confirmation could be to use mobile data and check the connection.
The above guide provides a simple approach to quickly identify the issue and get your server up and running. If the issue is not yet resolved, please contact cloud-platform@e2enetworks.com, and our team will help you resolve the issue.