how to deal with ipmitool sol session which looks frozen - ipmitool

I use ipmitool SOL session to get console logs from remote server. Initially session is responsive. If I hit enter, I can see login message to remote server like below.
[SOL Session operational. Use ~? for help]
<hostname> login:
But if I don't hit enter after activating session and try to press enter or any key, it does not do anything. I can see only this line:
[SOL Session operational. Use ~? for help]
I am not sure if the session becomes frozen or not. I can see help after pressing ~? but it is not helpful to resolve the issue. I don't see that login message again.
Is there way to generate some logs on this session without shutting off remote server ? And what are the ways to deal with frozen sol sessions ?
UPDATE
I create SOL sessions by using this command:
ipmitool -I lanplus -U <ipmi-username> -P <ipmi-password> -H <ipmi-ip> sol activate

Type "~." to quite the SOL session.
Reference: https://advantech-ncg.zendesk.com/hc/en-us/articles/360021053132-How-to-use-SOL-serial-over-lan-

Related

Able to authenticate with SSH with Github but somehow says "key is already in use"?

I have two ssh keys i've created, first one for my personal use and
the second one which I just created for work/school.
When I log into using git CLI using SSH with the second SSH key, it says
that i have successfully logged in like below
$ winpty gh auth login
? What account do you want to log into? GitHub.com
? You're already logged into github.com. Do you want to re-authenticate? Yes
? What is your preferred protocol for Git operations? SSH
? Upload your SSH public key to your GitHub account? C:\Users\dykim\.ssh\id_rsa.
pub
? Title for your SSH key: (GitHub CLI) second-key
? Title for your SSH key: future_proof
? How would you like to authenticate GitHub CLI? Login with a web browser
! First copy your one-time code: 0B1D-6370
Press Enter to open github.com in your browser...
✓ Authentication complete.
- gh config set -h github.com git_protocol ssh
✓ Configured git protocol
HTTP 422: Validation Failed (https://api.github.com/user/keys)
key is already in use
so somehow there isn't a problem to authenticating.
But I am worried that this will somehow pop up later and be a problem later when I am
working on my future projects for work.
What can I do to avoid this issue?
That seems similar to a pending reported issue #5299: "Spurious auth error when SSH key is already registered on account"
Steps to reproduce the behavior
Run gh auth login and select an SSH key that is already registered with the account
Get the above error, even though the key will work correctly
Expected vs actual behavior
I think there are a couple of ways that the handling of already registered keys could be improved:
Given the CLI app is granted full permission over the user's registered SSH keys, it could presumably list the already registered ones first and only attempt to register a new key if it wasn't already registered.
Then the error would only occur if the key was registered on a different account (or you uploaded it via the web browser while also attempting to register the CLI app, which would be an odd thing to do)
Customise the error message when this step fails to say something like "key already in use (Note: this error is expected if this SSH key was already registered on your account)"

"Error getting tty, exiting' displayed on trying to ssh as admin

My code is
c = Net::SSH.start("192.168.x.x", "admin", :password=>"xyz")
puts c.exec "sh run"
c.close
Executing this I get "Error getting tty, exiting". What is the issue here, please help me.
Thanks,
Jade
This is happening because admin user on remote host doesn't have shell associated with it, so when you login ssh is getting that error while running the command.
Login to the remote machine and set a valid shell for the admin user or use a different user who has valid shell associated with it.
Also its good practice to specify the full path of the binary that you need to invoke, so instead of 'sh' its better to us '/bin/sh'.

ERROR: (gcloud.compute.ssh) [/usr/bin/ssh] exited with return code [255]

I kept getting kicked out of my compute engine instance after a few seconds of idle with the indicated error (255).
I used 'gcloud compute ssh' to log in.
I am using the default firewall setting, which I believe would be good enough for ssh.
But if I am missing something, please so indicate and suggest the fix for this error.
Basically I can't get any efficient work done at this point having to ssh in so many times.
gcloud denies an ssh connection if there was a change in the setup, e.g.
after you changed your default zone or region, or you created another instance.
Then, you must update the ssh keys in your metadata by
sudo gcloud compute config-ssh
If this complains about different entries in your config file where your ssh key entries are stored, ~/.ssh/config, delete this file and execute the above command again.
If you have installed gcloud without sudo, you can omit sudo.
255 is the interactive ssh exit code for ssh failure - otherwise interactive ssh exits with the exit code of the last command executed in the ssh session.
The next time you get exit code 255 from ssh try running with --ssh-flag="-vvv" (more v's => more debugging output) and see if it helps track down connection problems.
For those who stop by this page. This helped me to solve the problem.
Try to the following:
Go to your Google and remove the SSH key for the server
Go to your google cloud console -> compute engine -> Metadata -> "SSH
keys" tab and click on edit. Here you can delete the ssh keys.
Run the gcloud command again
Click on the "Instances" link on the left side of your google cloud account, which will list down all the instances on the right side. Under
connect column, you will see "SSH" drop-down, click on "View cloud
Command" and this will bring a new dialog. Copy that command and run on your PC's terminal. This will let you SSH into the google compute engine.
It seems a feature/issue from Google Cloud Platform itself, we are going to continue checking it.
If the default network was edited, or if not using the default network, you may need to explicitly enable ssh access by adding a firewall-rule:
$ gcloud compute firewall-rules create --network=YOUR_NETWORK \
default-allow-ssh --allow tcp:22
After that, retry the 'gcloud compute ssh' command.
This is a real problem with very little documentation to dealing with it.
Sometime after creating the instance using the gcloud sdk ssh snippet provided via GCP console stopped working and continually errors with 255 making connecting to ssh on the instance only available through browser via GCP console for the compute instance in question. Not to mention this has happened to me on many different instances some without touching the default account permissions after initial setup and deployment which is overly frustrating. Cause for no reason it just stops working...works, then doesn't...
The only thing that worked for me was creating a new user to connect with through gcloud sdk! Be it Windows/PowerShell or Linux locally, using the following snippet:
gcloud compute ssh newuser-name#instance-name
That all per GCP documentation here: https://cloud.google.com/compute/docs/troubleshooting/troubleshooting-ssh
Everything else passed per suggestions in documentation - port 22 open with access meaning it has to be a a problem with the default users authorization_keys WHICH they provide absolutely no documentation on how to fix that - at least nothing I could find on fixing (not creating or deleting)
I've tried updating the account, tried deleting the user and credentials from the instance, nothing appears to work. using:
gcloud compute --project "project-name" ssh --zone "us-east4-a" "instance-name"
Just doesn't work...
- even tried 'gcloud compute config-ssh --force-key-file-overwrite' NOTHING WORKS...
But creating a new user works every time, and once the user is created you can keep using that user via gcloud sdk
It's a work around, and I hate work around's for things like this but for my sanity this works at least until I can figure out how to reset the default account permissions, so if anyone has any ideas there or can point me in a direction for that I'd more than appreciate it!
IT was my mistake stating that the default firewall would allow all connections into an instance. The contrary turned out to be true. Please refer to an appropriate firewall rule must be set up to allow connection into an instance
Anh-
If you have Identity-Aware Proxy (IAP) enabled for your setup, try adding the --tunnel-through-iap option to the gcloud compute ssh command.
$ gcloud compute ssh --zone <zone> --project <project> --tunnel-through-iap <instance-name>
More information for people landing on this page, if you're using preemptible instances to save some compute costs, that could also be the reason for getting kicked out like this. Your instance may have just randomly stopped.
In my case, the I had created a bootable disk for the VM without adding the information of what source-image it needs to have. Because of this, even though the instance was coming up alright and ssh-allow rule was there, the VM was not booting up.
Finally added the source image to the disk and I was able to ssh into the VM.
Hope this helps for someone.
I had the same error . i restarted the VM instance and ssh workis fine
I had the problem where after clicking on the SSH button it would keep trying to establish a connection and fail. After long struggle I resolved it by adding Service Account User role to myself. If your account was created after the VM instance was created, it might result in this situation.
I know this was opened a long time ago, but for a more recent update on this topic. I had the same trouble connecting via ssh. It was giving the error code 225. Obviously there was a connectivity issue. There was already a firewall rule set under VPC network-> Firewall to allow ssh. However, to fix this problem I had to go to the specific network and create a rule under the network Firewall Rules. VPC network details -> FIREWALL RULES and create an inbound TCP rule for port 22.
if you are having a problem trying to access you g-cloud VM instance from your computer terminal remotely, and are getting the error code 255,the problem is that the ssh protocols in your computer are wrong or not updated.
In this case the best way to fix it is to go to your home directory (in your computer) check the hidden files and find the folder ".ssh" .Just delete this folder and re-open your bash terminal. Then run again your gcloud vm command.
Example:
you#your_computer:~$ gcloud beta compute ssh --zone "us-central1-a" "your_VM_name" --project "your_project_name"
You should this time instead of getting the error 255 code, the messages below:
WARNING: The private SSH key file for gcloud does not exist.
WARNING: The public SSH key file for gcloud does not exist.
WARNING: You do not have an SSH key for gcloud.
WARNING: SSH keygen will be executed to generate a key.
This tool needs to create the directory [/home/your_name/.ssh] before being able to
generate SSH keys.
Do you want to continue (Y/n)?
Type "Y" and gcloud will setup the new protocols by creating a brand new updated .ssh file.
After that you should be able to access your VM with your gcloud command without any problem.
That should solve the problem
Cheers
https://blackpearlmatrix.com
had the exact same symptoms - in my case the reason appeared to be the following. I was using root user + ssh key whereas root login is by default disabled in /etc/ssh/sshd_config (PermitRootLogin property).
I eventually had to delete my instance and make a new one with the same disk. See https://cloud.google.com/compute/docs/troubleshooting/troubleshooting-ssh#use_your_disk_on_a_new_instance for details.
For me, my other teammates were able to login into the machine, but not me. So I asked them to create a user of my name with sudo rights, logged into serial console and changed passwordAuthentication to yes followed by sudo service ssh restart (for few this could be sudo service sshd restart.)
Post this I was able to login with
ssh -o PreferredAuthentications=password username#publicIP -p 22
This trick worked fine for me.
Reinitializing the gcloud with "gcloud init" and generating new ssh keys resolved the problem for me.
I had same issue.
I had connected the serial control and had checked logs. and there was some error log like "there is no disk space". Then I had resized disk as written in this document.
Now I am able to connect to instance with ssh.
Try switching to a different Internet connection
So, I was getting the same error but in my case I was not able to log in to the instance at all.
(base) girish#girish:~$ gcloud beta compute ssh --zone "asia-east1-b" "fp-1" --project "fp-public"
ssh: connect to host 12.345.678.90 port 22: Resource temporarily unavailable
ERROR: (gcloud.beta.compute.ssh) [/usr/bin/ssh] exited with return code [255].
(base) girish#girish:~$ gcloud beta compute ssh --ssh-flag='-vvv' --zone "asia-east1-b" "fp-1" --project "fp-public"
OpenSSH_7.6p1 Ubuntu-4ubuntu0.3, OpenSSL 1.0.2n 7 Dec 2017
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug2: resolving "12.345.678.90" port 22
debug2: ssh_connect_direct: needpriv 0
debug1: Connecting to 12.345.678.90 [12.345.678.90] port 22.
[debug1: connect to address 12.345.678.90 port 22: Resource temporarily unavailable
ssh: connect to host 12.345.678.903 port 22: Resource temporarily unavailable
ERROR: (gcloud.beta.compute.ssh) [/usr/bin/ssh] exited with return code [255].
What worked for me:
I tried reinstalling lots of things and re-initializing various config and then landed on a thread which suggest to change the Internet network you are using and it worked!!
It's possible you have a rule that only allows whiltelisted IPs to ssh into a gcloud VM. So you may have forgotten to enable your work VPN or out of your work's office IP.
Try restarting your computer.
I got the same error and tried gcloud config ssh as mentioned previously to no avail. I then checked that the IDs and roles of serviceaccount and developer had 'editor' permissions, and that was fine. I started a new instance and logged out of all of my other google accounts and it still threw the error. Then, I restarted my computer and did not log back into my other google accounts. That fixed it.
When using IAP, GCP stores the key in instance metadata and then propagate
that to the ~/.ssh/authorized_keys file.
You might get the error OP talks about when you remove the key from the ~/.ssh/authorized_keys file and it's still in the instance metadata. Reason being:
GCP check that the user, key combo that you are using to ssh is already in the instance metadata.
It assumes that the exists in the ~/.ssh/authorized_keys file for that user and doesn't propagate the key.
As the key doesn't exist in ~/.ssh/authorized_keys file for whatever reason (you deleted it, someone else deleted it etc. etc.) - you get access denied.
If this is the case with you, then fix is simple: remove the instance metadata entry for that user, key combo (have attached an image for ref, just click X and remove your faulty key) and try ssh again
What worked for me was turning my firewall on. (On a Mac, ssh'ing into a gcp instance).
In another instance of the error, my connection worked fine when I was on ethernet, but not when I was on wifi. Switching back to ethernet allowed me to connect again.
In my case sorted out the issue after restarting the VM.
if you are able to access the VM previously and suddenly giving SSH issues, give it a try by restarting.
Permission wise check whether you have IAP-secured Tunnel User
gcloud compute ssh --zone "your_zone" "instance_name" --tunnel-through-iap --project "project_name"
If this not works check with the GCP built-in SSH client, and click open in browser window.
Hope this help !!!

jsch + running multiple command in shell after SU and then close channal

My requirement is as follow:
I have to login to Unix box using my credentials and once login, I have to do su to different user. I need to provide password and reason for scsu command.
once su successful, I have to run set of commands one after another as that user.
On completion of executions, close channel and session both.
I tried to use Shell channel but I am able to fire scsu only ... need help to complete remaining requirement of executions of command and closing channel

SSH Expect Password Issue with Login

Hi I've the following script that make an ssh login to my server.
spawn ssh presnetwork#192.168.244.14
expect "*(yes/no)?"
send "yes"
expect "password:"
send "pwd\n"
close
it works fine but it doesn't pass 'pwd' value to system, so script goes timeout and quit.
Any suggestions?
You could try with "KbdInteractiveAuthentication" set to "no"
(ssh -o KbdInteractiveAuthentication="no" presnetwork#192....). SSH by default uses Keyboard Interactive Authentication, which is something expect might not understand.
I would strongly recommend that you use public key authentication instead (as already recommended by Flo). It is way easier to handle, and way more secure, and way more comfortable. If you are just looking for a way to login to a remote server without having to enter the password everytime, take a look at ssh-agent, which will store the password for you after you entered it once in your desktop session. If you really don't want to enter your password, use pam_ssh, where your desktop login password will be used.
By default, the expect command is not yet installed. So, you to install it to acquire correct output.