You are here

ssh_exchange_identification: read: Connection reset by peer

Printer-friendly versionPrinter-friendly version

When connecting from outside using ssh, several failed login attempts in a row may produce an error such as:

ssh_exchange_identification: read: Connection reset by peer

This message can appear for a number of reasons, but in particular it may mean that your ssh logins are now being blocked for security reasons. This block is triggered automatically whenever several login failures are made in a short space of time. If this happens to you, wait a while then try again - the block is only temporary.

The block is triggered by only a few login failures. (The exact number varies, since OS platforms and ssh implementations do not all behave identically.)

These temporary blocks help to defeat brute force attempts to guess your password. Our externally accessible machines are under constant attack, so we have to take steps to protect our machines, our data and our reputation.

To avoid being blocked, install Kerberos on your home machine. Kerberos lets you authenticate to before making a login attempt. This is a far more secure way of connecting, and since it avoids SSH password prompts, it avoids the automatic blocks. (Note though that this trick does not work on our NX service.)

Find out more at these help pages:

Last reviewed: 

System Status

Home dirs (AFS)
Other services
Scheduled downtime

Choose a topic