Home » ssh_exchange_identification: read: Connection reset by peer

ssh_exchange_identification: read: Connection reset by peer

Solutons:


The abrupt change could be the result of a change in the configuration file on the servers sshd configuration, but you indicate cannot check or alter that without admin right. You can still try the following if the server’s admins cannot be reached (in time).

Your log only indicates the local version string, you should check the versions of sshd running on the server and the intermediate machine.

If these versions differ (especially between the local machine and the server and less between the intermediate machine and the server) there might be some negotiation incompatibility, this has happened before in ssh. The solution used to be to shorten the Ciphers, HostKeyAlgorithms and/or MACs entries, either on the commandline (ssh -c aes256-ctr, etc.) or on in your /etc/ssh/ssh_config.

You should look in the debug information (from connecting via the intermediate to the server) for appropriate values as argument for the -c/Ciphers, -o HostKeyAlgorithms/HostKeyAlgorithms and -m/MACs commandline resp. ssh_config changes.

I haven’t had this problem myself for a while, but IIRC when I did it was enough to manually force the Ciphers and HostKeyAlgorithms setting, after which I could update the server’s sshd version and the problem went away.

You may have been banned by fail2ban or denyhosts. In such a case (and also to check it), if you don’t want to bother with your server provider assistance, you need to log into your server from another IP address : e.g. another server, or a friend’s home connection, or a wifi hot spot, or using SSH with TOR.

Once logged in, check that your IP address indeed appears in /etc/hosts.deny (on the server side). If so, then fail2ban or denyhosts must be the culprit indeed.

See answers to this question for the procedure to prevent denyhosts to block your address continuously. For fail2ban find your ip with iptables -L --line-number and unban you ip with iptables -D <chain> <chain number>, you check details on howtoforge.

You may want to add your IP address to fail2ban and denyhosts whitelists (respectively /etc/fail2ban/jail.conf, line ignoreip, and /var/lib/denyhosts/allowed-hosts, create it if needed (but beware that the path may be different on your distribution)) to prevent the issue to happen again.

On the host server, remove the ssh pub.key located here: ~/.ssh/authorized_keysfor your mac. Then tail -f /var/log/auth.log while you open another terminal and try to ssh again ssh -v me@server. If you are prompted for a password then there was a problem with your ssh key. If you are still seeing the ‘ssh_exchange_identification: read: Connection reset by peer’ response, then you should be able to identify what the problem is from the log entry in the ‘/var/log/auth.log’ file after your failed attempt to login.

If you still failed to connect, post the logged entry from the auth file here and I’ll revise my answer.

Related Solutions

Joining bash arguments into single string with spaces

[*] I believe that this does what you want. It will put all the arguments in one string, separated by spaces, with single quotes around all: str="'$*'" $* produces all the scripts arguments separated by the first character of $IFS which, by default, is a space....

AddTransient, AddScoped and AddSingleton Services Differences

TL;DR Transient objects are always different; a new instance is provided to every controller and every service. Scoped objects are the same within a request, but different across different requests. Singleton objects are the same for every object and every...

How to download package not install it with apt-get command?

Use --download-only: sudo apt-get install --download-only pppoe This will download pppoe and any dependencies you need, and place them in /var/cache/apt/archives. That way a subsequent apt-get install pppoe will be able to complete without any extra downloads....

What defines the maximum size for a command single argument?

Answers Definitely not a bug. The parameter which defines the maximum size for one argument is MAX_ARG_STRLEN. There is no documentation for this parameter other than the comments in binfmts.h: /* * These are the maximum length and maximum number of strings...

Bulk rename, change prefix

I'd say the simplest it to just use the rename command which is common on many Linux distributions. There are two common versions of this command so check its man page to find which one you have: ## rename from Perl (common in Debian systems -- Ubuntu, Mint,...

Output from ls has newlines but displays on a single line. Why?

When you pipe the output, ls acts differently. This fact is hidden away in the info documentation: If standard output is a terminal, the output is in columns (sorted vertically) and control characters are output as question marks; otherwise, the output is...

mv: Move file only if destination does not exist

mv -vn file1 file2. This command will do what you want. You can skip -v if you want. -v makes it verbose - mv will tell you that it moved file if it moves it(useful, since there is possibility that file will not be moved) -n moves only if file2 does not exist....

Is it possible to store and query JSON in SQLite?

SQLite 3.9 introduced a new extension (JSON1) that allows you to easily work with JSON data . Also, it introduced support for indexes on expressions, which (in my understanding) should allow you to define indexes on your JSON data as well. PostgreSQL has some...

Combining tail && journalctl

You could use: journalctl -u service-name -f -f, --follow Show only the most recent journal entries, and continuously print new entries as they are appended to the journal. Here I've added "service-name" to distinguish this answer from others; you substitute...

how can shellshock be exploited over SSH?

One example where this can be exploited is on servers with an authorized_keys forced command. When adding an entry to ~/.ssh/authorized_keys, you can prefix the line with command="foo" to force foo to be run any time that ssh public key is used. With this...

Why doesn’t the tilde (~) expand inside double quotes?

The reason, because inside double quotes, tilde ~ has no special meaning, it's treated as literal. POSIX defines Double-Quotes as: Enclosing characters in double-quotes ( "" ) shall preserve the literal value of all characters within the double-quotes, with the...

What is GNU Info for?

GNU Info was designed to offer documentation that was comprehensive, hyperlinked, and possible to output to multiple formats. Man pages were available, and they were great at providing printed output. However, they were designed such that each man page had a...

Set systemd service to execute after fstab mount

a CIFS network location is mounted via /etc/fstab to /mnt/ on boot-up. No, it is not. Get this right, and the rest falls into place naturally. The mount is handled by a (generated) systemd mount unit that will be named something like mnt-wibble.mount. You can...

Merge two video clips into one, placing them next to each other

To be honest, using the accepted answer resulted in a lot of dropped frames for me. However, using the hstack filter_complex produced perfectly fluid output: ffmpeg -i left.mp4 -i right.mp4 -filter_complex hstack output.mp4 ffmpeg -i input1.mp4 -i input2.mp4...

How portable are /dev/stdin, /dev/stdout and /dev/stderr?

It's been available on Linux back into its prehistory. It is not POSIX, although many actual shells (including AT&T ksh and bash) will simulate it if it's not present in the OS; note that this simulation only works at the shell level (i.e. redirection or...

How can I increase the number of inodes in an ext4 filesystem?

It seems that you have a lot more files than normal expectation. I don't know whether there is a solution to change the inode table size dynamically. I'm afraid that you need to back-up your data, and create new filesystem, and restore your data. To create new...

Why doesn’t cp have a progress bar like wget?

The tradition in unix tools is to display messages only if something goes wrong. I think this is both for design and practical reasons. The design is intended to make it obvious when something goes wrong: you get an error message, and it's not drowned in...