Multiple SSH tunnel sessions to the same host

I am unable to establish multiple ssh tunnel sessions to a bastion node. I am able to do so using another SSH app but not with Core Tunnel/Shell. I have in .ssh/config

Host *
GSSAPIAuthentication no
PubkeyAcceptedKeyTypes +rsa-sha2-256,rsa-sha2-512
AddKeysToAgent yes
ControlMaster auto
ControlPath ~/.ssh/ssh-%C

What can you suggest?

Can you provide some more details on what other tool that is, how those tunnels look like, ports, host etc.?


I regularly run multiple tunnels to the same server, so what ever problem you're having, it's something more subtle than Core Tunnel simply not supporting multiple tunnels.

Are you creating all your tunnels in one Preset, or creating separate presets to the same server for each tunnel? I do the former all day every day, and I think I have successfully done the latter on occasion, but I can't check because I would have done that from the office and due to COVID I'm not going to be there for some time :slightly_frowning_face:

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Hello, the ssh app I used which is no longer in distribution is vSSH on OSX. With vSSH I can open two ssh connections to a bastion host on port 22. This is my jump box to internal hosts. With CoreShell when I open a ssh terminal and try another I get no connection it just times out.

I feel CoreShell is using my ~/.ssh/config because if I remove the settings posted above I cannot connect to my bastion at all. So I should get multiplexing. I am not sure if I am using one Preset how can I tell?

Not an issue for me with Core Shell or iTerm2


Host *
IdentityFile ~/.ssh/id_rsa
ServerAliveInterval 240
ServerAliveCountMax 2
TCPKeepAlive yes

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Thanks Mikael, able to do multiple connections now.