netcup wiki


Using the rescue system

How to utilize the rescue system to address server issues

netcup servers are known for their high reliability. However, sometimes network problems can still occur. If you are experiencing:

  • Elevated ping times of 100 milliseconds or more
  • Packet loss on the route to the vServer, possibly even at the last node
  • Very long boot times for the rescue system (5 to 10 minutes or more; this suggests a network problem)

These could be indicators of issues. In this case, we recommend checking with MTR and the rescue system.

1. Checking with MTR

If booting via the rescue system is not possible even after a longer wait, please contact support directly with this information, your customer number, and the server name and/or IP address

Boot your server into the rescue system. You can find the rescue system in the Server Control Panel (SCP) under "Media -> Rescue System".

Your server IP may be found under "Network" in the SCP.

Use MTR (My Traceroute) or WIN-MTR to check if there is packet loss on the route to the nodes. Please carry out at least 500 pings on both the server and the corresponding host using the following terminal command:

mtr <server_ip>

2. Checking with Iperf3

Next, run Iperf3 via Terminal. This provides us with information about the connection to and from your server:

I am using IPv4 First, execute this command:

iperf3 -c -p 5200 -P 10 -4

Then, execute this command:

iperf3 -c -p 5200 -P 10 -4 -R

I am using IPv6 First, execute this command:

iperf3 -c -p 5200 -P 10 -6

Then, execute this command:

iperf3 -c -p 5200 -P 10 -6 -R

3. Reporting to netcup

Get in touch with our support. The ticket should include:

  • The customer number
  • The server name and/or IP address
  • The output from MTR
  • The output from Iperf3
  • Information on whether the rescue system was booted

To assist us in processing your ticket, please provide the data output by MTR and Iperf3 as a text file attachment. We will then process your request as quickly as possible.

Last update: 20/09/2023