Score:1

Cannot connect to existing remote server over SSH on new Ubuntu install

ph flag

I built a brand new PC and am running Ubuntu 20.04.3 I have an existing server that I can connect to from every other computer I use, but when I try to ssh into it from my new PC it stalls out after debug1: Sending env LANG = en_US.UTF-8.

What is weird is that it does connect 1 out of about 15-20 attempts. I'm confused, it would make more sense if I could not connect from anywhere but this new install is the only one that gives me issues.

Where can I start to look, Im lost on this one.

EDIT I think its the QoS headers on the RaspberryPi sshd_config Not sure why only Ubuntu 20.04 is having an issue with it, but it seems that setting IPQoS 0x00 in the config fixes it.

This is the output I see:

user@nebula:~$ ssh -p 2215 [email protected] -v
OpenSSH_8.2p1 Ubuntu-4ubuntu0.3, OpenSSL 1.1.1f  31 Mar 2020
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: include /etc/ssh/ssh_config.d/*.conf matched no files
debug1: /etc/ssh/ssh_config line 21: Applying options for *
debug1: Connecting to 192.168.1.11 [192.168.1.11] port 2215.
debug1: Connection established.
debug1: identity file /home/user/.ssh/id_rsa type -1
debug1: identity file /home/user/.ssh/id_rsa-cert type -1
debug1: identity file /home/user/.ssh/id_dsa type -1
debug1: identity file /home/user/.ssh/id_dsa-cert type -1
debug1: identity file /home/user/.ssh/id_ecdsa type -1
debug1: identity file /home/user/.ssh/id_ecdsa-cert type -1
debug1: identity file /home/user/.ssh/id_ecdsa_sk type -1
debug1: identity file /home/user/.ssh/id_ecdsa_sk-cert type -1
debug1: identity file /home/user/.ssh/id_ed25519 type -1
debug1: identity file /home/user/.ssh/id_ed25519-cert type -1
debug1: identity file /home/user/.ssh/id_ed25519_sk type -1
debug1: identity file /home/user/.ssh/id_ed25519_sk-cert type -1
debug1: identity file /home/user/.ssh/id_xmss type -1
debug1: identity file /home/user/.ssh/id_xmss-cert type -1
debug1: Local version string SSH-2.0-OpenSSH_8.2p1 Ubuntu-4ubuntu0.3
debug1: Remote protocol version 2.0, remote software version OpenSSH_7.9p1 Raspbian-10+deb10u2+rpt1
debug1: match: OpenSSH_7.9p1 Raspbian-10+deb10u2+rpt1 pat OpenSSH* compat 0x04000000
debug1: Authenticating to 192.168.1.11:2215 as 'user'
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: algorithm: curve25519-sha256
debug1: kex: host key algorithm: ecdsa-sha2-nistp256
debug1: kex: server->client cipher: [email protected] MAC: <implicit> compression: none
debug1: kex: client->server cipher: [email protected] MAC: <implicit> compression: none
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:nwATOKppUhvgXjD991ySsnsdmmOxS2aVbmE8wFh0lKw
debug1: Host '[192.168.1.11]:2215' is known and matches the ECDSA host key.
debug1: Found key in /home/user/.ssh/known_hosts:1
debug1: rekey out after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: rekey in after 134217728 blocks
debug1: Will attempt key: /home/user/.ssh/id_rsa 
debug1: Will attempt key: /home/user/.ssh/id_dsa 
debug1: Will attempt key: /home/user/.ssh/id_ecdsa 
debug1: Will attempt key: /home/user/.ssh/id_ecdsa_sk 
debug1: Will attempt key: /home/user/.ssh/id_ed25519 
debug1: Will attempt key: /home/user/.ssh/id_ed25519_sk 
debug1: Will attempt key: /home/user/.ssh/id_xmss 
debug1: SSH2_MSG_EXT_INFO received
debug1: kex_input_ext_info: server-sig-algs=<ssh-ed25519,ssh-rsa,rsa-sha2-256,rsa-sha2-512,ssh-dss,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521>
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey,password
debug1: Next authentication method: publickey
debug1: Trying private key: /home/user/.ssh/id_rsa
debug1: Trying private key: /home/user/.ssh/id_dsa
debug1: Trying private key: /home/user/.ssh/id_ecdsa
debug1: Trying private key: /home/user/.ssh/id_ecdsa_sk
debug1: Trying private key: /home/user/.ssh/id_ed25519
debug1: Trying private key: /home/user/.ssh/id_ed25519_sk
debug1: Trying private key: /home/user/.ssh/id_xmss
debug1: Next authentication method: password
[email protected]'s password: 
debug1: Authentication succeeded (password).
Authenticated to 192.168.1.11 ([192.168.1.11]:2215).
debug1: channel 0: new [client-session]
debug1: Requesting [email protected]
debug1: Entering interactive session.
debug1: pledge: network
debug1: client_input_global_request: rtype [email protected] want_reply 0
debug1: Sending environment.
debug1: Sending env LANG = en_US.UTF-8
hr flag
You may get more information by increasing the debug level (`-vv` or `-vvv`)
ph flag
I didnt even know that was a thing! I will try it now. ty
ph flag
@steeldriver if I do -vvv it let me right in.... Is it a timing thing or too much data? It seems like it eventually connects if I retry 20 times. But almost never on the first several, the inconsistency confuses me.
ph flag
@guiverc Sorry it was a typo, I will correct, its Ubuntu 20.04.3
hr flag
Sorry I don't know why that would be
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