Hello, I'm looking for your insight about the log below. We have an SFTP server (IBM Sterling File Gateway) and we're connecting from an OpenSSH SFTP client but something fails during KEX. Complete client-side debug output is below, but I believe the relevant part is: debug1: kex: server->client cipher: aes192-cbc MAC: hmac-sha1 compression: none debug1: kex: client->server cipher: aes192-cbc MAC: hmac-sha1 compression: none debug3: send packet: type 30 debug1: sending SSH2_MSG_KEX_ECDH_INIT debug1: expecting SSH2_MSG_KEX_ECDH_REPLY debug3: receive packet: type 1 Received disconnect from 1.2.3.4 port 32:2: Failed to read binary packet data! Any suggestions about what's failing, and what the cause might be? We're trying to figure out where to go in our troubleshooting, and do not understand the meaning of this debug output. Thanks! Complete debug output (obfuscated to remove confidential data): [root@client ~]# sftp -vvvv -oport=32 SOMEUSER@xxxxxxxxxxxxxxxxxxx OpenSSH_7.2p2, OpenSSL 1.0.2h 3 May 2016 debug1: Reading configuration data /etc/ssh/ssh_config debug2: resolving "some.server.we.have" port 32 debug2: ssh_connect_direct: needpriv 0 debug1: Connecting to some.server.we.have [1.2.3.4] port 32. debug1: Connection established. debug1: permanently_set_uid: 0/0 debug1: identity file /root/.ssh/id_rsa type 1 debug1: key_load_public: No such file or directory debug1: identity file /root/.ssh/id_rsa-cert type -1 debug1: key_load_public: No such file or directory debug1: identity file /root/.ssh/id_dsa type -1 debug1: key_load_public: No such file or directory debug1: identity file /root/.ssh/id_dsa-cert type -1 debug1: key_load_public: No such file or directory debug1: identity file /root/.ssh/id_ecdsa type -1 debug1: key_load_public: No such file or directory debug1: identity file /root/.ssh/id_ecdsa-cert type -1 debug1: key_load_public: No such file or directory debug1: identity file /root/.ssh/id_ed25519 type -1 debug1: key_load_public: No such file or directory debug1: identity file /root/.ssh/id_ed25519-cert type -1 debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_7.2 debug1: Remote protocol version 2.0, remote software version Welcome To Ceridian debug1: no match: Welcome To Ceridian debug2: fd 3 setting O_NONBLOCK debug1: Authenticating to some.server.we.have:32 as 'SOMEUSER' debug3: put_host_port: [some.server.we.have]:32 debug3: hostkeys_foreach: reading file "/root/.ssh/known_hosts" debug3: send packet: type 20 debug1: SSH2_MSG_KEXINIT sent debug3: receive packet: type 20 debug1: SSH2_MSG_KEXINIT received debug2: local client KEXINIT proposal debug2: KEX algorithms: curve25519-sha256@xxxxxxxxxx,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,ext-info-c debug2: host key algorithms: ecdsa-sha2-nistp256-cert-v01@xxxxxxxxxxx,ecdsa-sha2-nistp384-cert-v01@xxxxxxxxxxx,ecdsa-sha2-nistp521-cert-v01@xxxxxxxxxxx,ssh-ed25519-cert-v01@xxxxxxxxxxx,ssh-rsa-cert-v01@xxxxxxxxxxx,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519,rsa-sha2-512,rsa-sha2-256,ssh-rsa debug2: ciphers ctos: chacha20-poly1305@xxxxxxxxxxx,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@xxxxxxxxxxx,aes256-gcm@xxxxxxxxxxx,aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc debug2: ciphers stoc: chacha20-poly1305@xxxxxxxxxxx,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@xxxxxxxxxxx,aes256-gcm@xxxxxxxxxxx,aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc debug2: MACs ctos: umac-64-etm@xxxxxxxxxxx,umac-128-etm@xxxxxxxxxxx,hmac-sha2-256-etm@xxxxxxxxxxx,hmac-sha2-512-etm@xxxxxxxxxxx,hmac-sha1-etm@xxxxxxxxxxx,umac-64@xxxxxxxxxxx,umac-128@xxxxxxxxxxx,hmac-sha2-256,hmac-sha2-512,hmac-sha1 debug2: MACs stoc: umac-64-etm@xxxxxxxxxxx,umac-128-etm@xxxxxxxxxxx,hmac-sha2-256-etm@xxxxxxxxxxx,hmac-sha2-512-etm@xxxxxxxxxxx,hmac-sha1-etm@xxxxxxxxxxx,umac-64@xxxxxxxxxxx,umac-128@xxxxxxxxxxx,hmac-sha2-256,hmac-sha2-512,hmac-sha1 debug2: compression ctos: none,zlib@xxxxxxxxxxx,zlib debug2: compression stoc: none,zlib@xxxxxxxxxxx,zlib debug2: languages ctos: debug2: languages stoc: debug2: first_kex_follows 0 debug2: reserved 0 debug2: peer server KEXINIT proposal debug2: KEX algorithms: diffie-hellman-group1-sha1,diffie-hellman-group14-sha1,diffie-hellman-group-exchange-sha1,diffie-hellman-group-exchange-sha256,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521 debug2: host key algorithms: ssh-rsa debug2: ciphers ctos: aes256-cbc,aes192-cbc debug2: ciphers stoc: aes256-cbc,aes192-cbc debug2: MACs ctos: hmac-sha1 debug2: MACs stoc: hmac-sha1 debug2: compression ctos: none debug2: compression stoc: none debug2: languages ctos: debug2: languages stoc: debug2: first_kex_follows 0 debug2: reserved 0 debug1: kex: algorithm: ecdh-sha2-nistp256 debug1: kex: host key algorithm: ssh-rsa debug1: kex: server->client cipher: aes192-cbc MAC: hmac-sha1 compression: none debug1: kex: client->server cipher: aes192-cbc MAC: hmac-sha1 compression: none debug3: send packet: type 30 debug1: sending SSH2_MSG_KEX_ECDH_INIT debug1: expecting SSH2_MSG_KEX_ECDH_REPLY debug3: receive packet: type 1 Received disconnect from 1.2.3.4 port 32:2: Failed to read binary packet data! Disconnected from 1.2.3.4 port 32 Couldn't read packet: Connection reset by peer John Delisle | Solution Architecture | Ceridian HCM | w: 204.975.5909 / 204.414.1285 |c: 204.294.5529 Ceridian. Makes Work Life Better(tm) _______________________________________________ openssh-unix-dev mailing list openssh-unix-dev@xxxxxxxxxxx https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev