MacOS iMac cryosparc localhost web interface issue

I am able to connect with cryosparc master node using my iMAC, terminal shell bash. But , when I try to connect using web interface - It give error

This site can’t be reached
localhost refused to connect.

Have you established a port forwarding channel between your iMac and CryoSPARC master node?

yes. It is connected to the master node.

What was the full ssh command you used to forward the local port?

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Is CryoSPARC running? (cryosparcm start on CryoSPARC master system)

Just connecting via SSH is not sufficient, you need to connect in a particular way… assuming the default ports were used when CryoSPARC was installed…

ssh -L [port]:[cryoSPARCmasterIPaddress]:39000 [username]@[cryoSPARCmasterIPaddress]

The connect with: localhost:[port] in your web browser. So, e.g.:

ssh -L 4567: cryosparc@ then localhost:4567

(That IP is just an example. Although IIRC, it’s one of the Google DNS servers)

Command I used for SSH
ssh -Y cryosparc@IP address

Cryosparc was running. Message is below-
CryoSPARC master started.
From this machine, access cryoSPARC and cryoSPARC Live at

This command and connection will not establish the necessary ssh tunnel. You may want to instead try:

ssh -L 61000:localhost:39000 cryosparc@ipaddress

and enter into your web browser’s address bar
In the ssh command, the second number must match the CRYOSPARC_BASE_PORT (--port during installation) of your CryoSPARC instance. The first number should be an “unused” port on your iMac, and does not necessarily have to match the second number.
For advanced parameters, see our guide.

The imac is on same network as the master node where cryosparc is installed. and other iMac in lab are ok with this command that I used but only this iMac is giving issues.
I will try what you said also.
But the SSH was working. It was webinterface where I was not able to connect.

ssh -L 61000:localhost:39000 cryosparc@ipaddress
It worked. Thank You

The problem is not totally resolved yet.
using the command below, I am able to connect with one of master node at my workplace but not the other one.
ssh -L 61000:localhost:39000 cryosparc@IP address
ssh -L 61000:localhost:39000 cryosparc@IP address The authenticity of host ‘IP address (IP address )’ can’t be established.

ED2shh19 key fingerprint is SHA256:jasdsadddBWsBlEtiU80I885O6QrPCGdJm9HAfBSkAsk.

This key is not known by any other names

Are you sure you want to continue connecting (yes/no/[fingerprint])? yes

Warning: Permanently added 'IP address ’ (ED32419) to the list of known hosts.

cryosparc@IP address 's password:

Permission denied, please try again.

@vijayverma Are you trying to connect to two different CryoSPARC master instances?
Please keep in mind that you cannot use the same local port 61000 to simultaneously forward to distinct remote server ports.

You may have typed an incorrect password.

I am not connecting to both master nodes both simultaneously.
password is correct as I am able to connect with this master node with my personal computer using same password.
Is there any way I can connect from master node to this computer (lab computer that is on same network as the master node) ?

I have no better explanation for the output you posted than that the incorrect password was supplied, maybe due to a typo or inadvertent activation of the caps lock.

There probably is, but there may be security implications. You may want to

  • determine the purpose of this connection, such as data exchange or remote command execution
  • search for relevant instructions specific to your operating system

ssh -N -f -L localhost:39000:localhost:39000 cryosparc@IP address
Is it ok for connecting master node to my lab PC. This is for remote command execution.