For a database course that I'm in, the professor has tasked us with setting up several VM MySQL servers and remote connections. I've found proper documentation to solve most of my problems, but I've pored over docs trying to find a solution to my latest issue.
I've set up an Ubuntu VM on the Google Cloud Compute Engine. I installed a MySQL server to this VM instance, and I need to log in remotely from my laptop. I've followed this documentation https://cloud.google.com/solutions/mysql-remote-access and this youtube video https://www.youtube.com/watch?v=f5qQDm3ciDg.
However, I still get an Unable to Connect to Server message when I test my connection. What could I be overlooking that will help me connect?
Thanks!
So, I slammed my head against a wall for long enough to realize that ssh will be an easier solution than a direct connection.
So, at least for my Windows machine, these are the steps I followed to make the connection:
Download the sql server (You don't need to add a user unless necessary, and you don't change the bind-address in the config file).
Use PuTTYgen to create a private public key pair. Export the private key as an openssh format (in the export options)
Click the edit button on your VM instance then scroll down to the SSH key section.
Paste the public key into the text box (be sure to change the last comment portion to a username on the Linus VM)
Use the SSH connection on MySQL Workbench. Use the external IP of your VM as the first (ssh) host name and localhost as the second (SQL) host name. Input all other info as it is asked for.
I am trying to connect to Unix server from WinSCP commandline for the first time.
It closes with the the following error:
The server's host key was not found in the cache. You have no guarantee that the
server is the computer you think it is.
The server's rsa2 key fingerprint is:
ssh-rsa 1024 42:9e:c7:f4:7f:8b:50:10:6a:06:04:b1:d4:f2:04:6d
If you trust this host, press Yes. To connect without adding host key to the cac
he, press No. To abandon the connection press Cancel.
In the WinSCP commandline, it does not ask for any input (Yes or No). It closes with Authentication failed. If I connect through the WinSCP tool, I'll get the same error. However, I'll be able to press YES.
I also know that If I add -hostkey switch in the command line, I'll be able to connect. But, I don't want pass hostkey in my batch script as I will be connecting to various servers. So, my requirement is to pass "YES" input from the commandline in case of this error. Can someone help?
A host key fingerprint verification is a crucial step in securing your SSH connection. Even if you are using a set of sessions with your script, it does not excuse you. The fingerprint should be part of a set of information you have for each of the sessions (in addition to a hostname, an username and a password).
Skipping the fingerprint verification means that you lose any security and there's no point using an SSH/SFTP anymore.
Anyway, if you do not care about a security, you can use the -hostkey=* switch to unconditionally accept any host key.
Further references:
Where do I get SSH host key fingerprint to authorize the server?
Verifying the host key
I created an app called "world" following the instructions from:
https://blog.openshift.com/12-tips-for-hosting-wordpress-on-openshift/.
It's a hosted Wordpress blog, with PHP 5.4 scalable up to 1GB, with a Web Load Balancer and MySQL 5.5.
Everytime I try to check for the space used, I get the same error.
rhc show-app world --gears quota
Unable to connect to gear 54d48383fcf933f91f0000aa#54d48383fcf933f91f0000aa-laurapons.rhcloud.com
Unable to connect to gear 54d48383fcf933f91f0000a9#world-laurapons.rhcloud.com
Gear Cartridges Used Limit
------------------------ ------------------- ----- -----
54d48383fcf933f91f0000aa mysql-5.5 error 1 GB
54d48383fcf933f91f0000a9 haproxy-1.4 php-5.4 error 1 GB
I tried to restart the application (using restart and stop&start commands) but nothing seems to work.
I am also facing some other connection problems (probably related to the same issue):
I have the same problem when trying to clone the application with git clone:
ssh: connect to host world-laurapons.rhcloud.com port 22: Bad file number
fatal: Could not read from remote repository.
Please make sure you have the correct access rights and the repository exists.
And also with the rhc port-forward world
I copied the URL for git clone from the openshift online dashboard, and I can open the wordpress blog and see all the information, but somehow, I'm unable to access to the data.
I have already created a default Public Key and 2 authorisations (one to access through the browser and the other to access through RHC)...
What should I try?
How can I get the usage?
Do I need to set up anything else?
I am stuck... any suggestion?
Sounds like your SSH key is not working properly. Make sure you installed your keys and that they are working. Try running 'rhc setup'. If that still doesn't work try
ssh -vvv 54d48383fcf933f91f0000a9#world-laurapons.rhcloud.com
and look at the output.
You can also try using
ssh -i /path/to/your/ssh.key 54d48383fcf933f91f0000a9#world-laurapons.rhcloud.com
And see if that works (specifies what ssh key to use)
rhc with some ruby version will have issue with pageant (putty). I closed pageant, ran again rhc command then it worked.
After creating the instance, I can login using gcutil or ssh. I tried copy/paste from the ssh link listed at the bottom of the instance and get the same error message.
The permission denied error probably indicates that SSH private key authentication has failed. Assuming that you're using an image derived from the Debian or Centos images recommended by gcutil, it's likely one of the following:
You don't have any ssh keys loaded into your ssh keychain, and you haven't specified a private ssh key with the -i option.
None of your ssh keys match the entries in .ssh/authorized_keys for the account you're attempting to log in to.
You're attempting to log into an account that doesn't exist on the machine, or attempting to log in as root. (The default images disable direct root login – most ssh brute-force attacks are against root or other well-known accounts with weak passwords.)
How to determine what accounts and keys are on the instance:
There's a script that runs every minute on the standard Compute Engine Centos and Debian images which fetches the 'sshKeys' metadata entry from the metadata server, and creates accounts (with sudoers access) as necessary. This script expects entries of the form "account:\n" in the sshKeys metadata, and can put several entries into authorized_keys for a single account. (or create multiple accounts if desired)
In recent versions of the image, this script sends its output to the serial port via syslog, as well as to the local logs on the machine. You can read the last 1MB of serial port output via gcutil getserialportoutput, which can be handy when the machine isn't responding via SSH.
How gcutil ssh works:
gcutil ssh does the following:
Looks for a key in $HOME/.ssh/google_compute_engine, and calls ssh-keygen to create one if not present.
Checks the current contents of the project metadata entry for sshKeys for an entry that looks like ${USER}:$(cat $HOME/.ssh/google_compute_engine.pub)
If no such entry exists, adds that entry to the project metadata, and waits for up to 5 minutes for the metadata change to propagate and for the script inside the VM to notice the new entry and create the new account.
Once the new entry is in place, (or immediately, if the user:key was already present) gcutil ssh invokes ssh with a few command-line arguments to connect to the VM.
A few ways this could break down, and what you might be able to do to fix them:
If you've removed or modified the scripts that read sshKeys, the console and command line tool won't realize that modifying sshKeys doesn't work, and a lot of the automatic magic above can get broken.
If you're trying to use raw ssh, it may not find your .ssh/google_compute_engine key. You can fix this by using gcutil ssh, or by copying your ssh public key (ends in .pub) and adding to the sshKeys entry for the project or instance in the console. (You'll also need to put in a username, probably the same as your local-machine account name.)
If you've never used gcutil ssh, you probably don't have a .ssh/google_compute_engine.pub file. You can either use ssh-keygen to create a new SSH public/private keypair and add it to sshKeys, as above, or use gcutil ssh to create them and manage sshKeys.
If you're mostly using the console, it's possible that the account name in the sshKeys entry doesn't match your local username, you may need to supply the -l argument to SSH.
Ensure that the permissions on your home directory and on the home directory of the user on the host you're connecting to are set to 700 ( owning user rwx only to prevent others seeing the .ssh subdirectory ).
Then ensure that the ~/.ssh directory is also 700 ( user rwx ) and that the authorized_keys is 600 ( user rw ) .
Private keys in your ~/.ssh directory should be 600 or 400 ( user rw or user r )
I was facing this issue for long time. Finally it was issue of ssh-add. Git ssh credentials were not taken into consideration.
Check following command might work for you:
ssh-add
I had the same problem and for some reason The sshKeys was not syncing up with my user on the instance.
I created another user by adding --ssh_user=anotheruser to gcutil command.
The gcutil looked like this
gcutil --service_version="v1" --project="project" --ssh_user=anotheruser ssh --zone="us-central1-a" "inst1"
I just experienced a similar message [ mine was "Permission denied (publickey)"] after connecting to a compute engine VM which I just created. After reading this post, I decided to try it again.
That time it worked. So i see 3 possible reasons for it working the second time,
connecting the second time resolves the problem (after the ssh key was created the first time), or
perhaps trying to connect to a compute engine immediately after it was created could also cause a problem which resolves itself after a while, or
merely reading this post resolves the problem
I suspect the last is unlikely :)
I found this error while connecting ec2 instance with ssh.
and it comes if i write wrong user name.
eg. for ubuntu I need to use ubuntu as user name
and for others I need to use ec2-user.
You haven't accepted an answer, so here's what worked for me in PuTTY:
Without allowing username changes, i got this question's subject as error on the gateway machine.
You need to follow this instructions
https://cloud.google.com/compute/docs/instances/connecting-to-instance#generatesshkeypair
If get "Permission denied (publickey)." with the follow command
ssh -i ~/.ssh/my-ssh-key [USERNAME]#[IP_ADDRESS]
you need to modify the /etc/ssh/sshd_config file and add the line
AllowUsers [USERNAME]
Then restart the ssh service with
service ssh restart
if you get the message "Could not load host key: /etc/ssh/ssh_host_ed25519_key" execute:
ssh-keygen -A
and finally restart the ssh service again.
service ssh restart
I followed everything from here:
https://cloud.google.com/compute/docs/instances/connecting-to-instance#generatesshkeypair
But still there was an error and SSH keys in my instance metadata wasn't getting recognized.
Solution: Check if your ssh key has any new-line. When I copied my public key using cat, it added into-lines into the key, thus breaking the key. Had to manually check any line-breaks and correct it.
The trick here is to use the -C (comment) parameter to specify your GCE userid. It looks like Google introduced this change last in 2018.
If the Google user who owns the GCE instance is myname#gmail.com (which you will use as your login userid), then generate the key pair with (for example)
ssh-keygen -b521 -t ecdsa -C myname -f mykeypair
When you paste mykeypair.pub into the instance's public key list, you should see "myname" appear as the userid of the key.
Setting this up will let you use ssh, scp, etc from your command line.
Add ssh public key to Google cloud
cat ~/.ssh/id_rsa.pub
go and click your VM instances
edit VM instances
add ssh public key(from id_rsa.pub) in SSH keys area
ssh login from Git bash on your computer
ssh -i ~/.ssh/id_rsa tiennt#x.y.z.120
I have a BB (BitBucket) account for work and a BB account for my self and want to be able to access them both from one PC using TortoiseHg with SSH.
When you add the two keys to Pageant and then try to push to a repo that uses one of the accounts Pageant will pass the first SSH to BB and if it's a BB account SSH BB will accept it log the user in with the account related to that SSH key.
Now if that first SSH key is for the account that has access to the repo that's fine BUT IF that first SSH key was for the other account you will get an authorisation error.
There seems no way to pass the correct key to BB using TortoiseHg at all. And therefore I am constantly swapping SSH out of Pageant which clearly isn't ideal and I might as well drop SSH and use passwords. :(
Does anyone know of a way to get TortoiseHg to pass the correct SSH for that account?
As I was writing this question I happened to come across a solution! Now the reason I hadn't come across it before is it was for Git not Mecurial so I think that it's still worth posting this question and this solution to allow others in the same boat to easily find the solution. :)
The solution was from here: https://answers.atlassian.com/questions/150285/only-the-top-listed-private-key-in-pageant-is-used-offered-by-git-sourcetree-tortoisegit
Here is the important part:
One way to resolve this is to perform the same configuration in PuTTY
too to disambiguate what key to send (and therefore which user to
authenticate as).
Start PuTTY (download it from putty.org if you don't have it)
Type 'bitbucket.org' in the host name field
Go to Connection > SSH > Auth in the tree
Specify the key to use for the BB user
Go back to 'Session' in the tree
Type an alias name underneath 'Saved Sessions' (e.g. bb-user1) and Save
Repeat 2-6 for each BB user and save as a different session name
Then in your remote URLs, replace 'bitbucket.org' with the session
name (e.g. bb-user1) to disambiguate what SSH key to send first. This
is identical to using IdentityFile in OpenSSH.