[Bug 1971158] Re: ssh connect to server stop on "SSH2_MSG_KEXINIT sent"

[Gerald Skead]

Confirmed adding entry to .ssh/config solved it for me.

My example for each old host:

Host x.x.x.x
        HostkeyAlgorithms +ssh-rsa
PubkeyAcceptedAlgorithms +ssh-rsa

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Title:
  ssh connect to server  stop on "SSH2_MSG_KEXINIT sent"

Status in openssh package in Ubuntu:
  Won't Fix

Bug description:
  After upgrade on Ubuntu 22.04 i can't connect to several servers. Connecting stopped on  SSH2_MSG_KEXINIT sent
  ```
   ssh -vvv -o KexAlgorithms=diffie-hellman-group-exchange-sha256 -oHostKeyAlgorithms=+ssh-rsa  -X vld at sansa
  OpenSSH_8.9p1 Ubuntu-3, OpenSSL 3.0.2 15 Mar 2022
  debug1: Reading configuration data /home/ruslan/.ssh/config
  debug3: kex names ok: [diffie-hellman-group1-sha1]
  debug3: kex names ok: [diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1]
  debug3: kex names ok: [diffie-hellman-group1-sha1]
  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 *
  debug3: expanded UserKnownHostsFile '~/.ssh/known_hosts' -> '/home/ruslan/.ssh/known_hosts'
  debug3: expanded UserKnownHostsFile '~/.ssh/known_hosts2' -> '/home/ruslan/.ssh/known_hosts2'
  debug2: resolving "sansa" port 22
  debug3: resolve_host: lookup sansa:22
  debug3: ssh_connect_direct: entering
  debug1: Connecting to sansa [172.16.xx.xx] port 22.
  debug3: set_sock_tos: set socket 3 IP_TOS 0x10
  debug1: Connection established.
  debug1: identity file /home/ruslan/.ssh/id_rsa type -1
  debug1: identity file /home/ruslan/.ssh/id_rsa-cert type -1
  debug1: identity file /home/ruslan/.ssh/id_ecdsa type -1
  debug1: identity file /home/ruslan/.ssh/id_ecdsa-cert type -1
  debug1: identity file /home/ruslan/.ssh/id_ecdsa_sk type -1
  debug1: identity file /home/ruslan/.ssh/id_ecdsa_sk-cert type -1
  debug1: identity file /home/ruslan/.ssh/id_ed25519 type -1
  debug1: identity file /home/ruslan/.ssh/id_ed25519-cert type -1
  debug1: identity file /home/ruslan/.ssh/id_ed25519_sk type -1
  debug1: identity file /home/ruslan/.ssh/id_ed25519_sk-cert type -1
  debug1: identity file /home/ruslan/.ssh/id_xmss type -1
  debug1: identity file /home/ruslan/.ssh/id_xmss-cert type -1
  debug1: identity file /home/ruslan/.ssh/id_dsa type -1
  debug1: identity file /home/ruslan/.ssh/id_dsa-cert type -1
  debug1: Local version string SSH-2.0-OpenSSH_8.9p1 Ubuntu-3
  debug1: Remote protocol version 2.0, remote software version OpenSSH_5.3
  debug1: compat_banner: match: OpenSSH_5.3 pat OpenSSH_5* compat 0x0c000002
  debug2: fd 3 setting O_NONBLOCK
  debug1: Authenticating to sansa:22 as 'vld'
  debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts2: No such file or directory
  debug3: order_hostkeyalgs: no algorithms matched; accept original
  debug3: send packet: type 20
  debug1: SSH2_MSG_KEXINIT sent

  
  ```
  I'm checking connection on old version Ubuntu 20.04, it's working. Remote server use 
  KexAlgorithms=diffie-hellman-group-exchange-sha256 and HostKeyAlgorithms=ssh-rsa

  On Ubuntu 21.04 ssh was work.

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