keep connection alive

ceyhu...@gmail.com

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Jan 16, 2015, 8:20:46 AM1/16/15

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Is there a conf the keep connection alive or by default the connection lasts ever.

or is there way like cmd.write(noop) to keep connection alive.

i suspect long running connections are dropped {still not sure but looking into}.

what i do is

ssh = new SSHClient();
ssh.addHostKeyVerifier(new PromiscuousVerifier());
ssh.connect(s.getHost());
authenticate();
session = ssh.startSession();
session.allocateDefaultPTY();
cmd = session.exec(command);

Jeroen van Erp

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Jan 16, 2015, 8:40:57 AM1/16/15

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Hi,

I'm just working on adding that. Shekhar, the previous maintainer, built a heartbeat already, but the problem I found with that is that it doesn't check for "responses" from the server. The heartbeat just tells the server that the client is still there, but for the client there is no way to know whether the server is still there currently.

Expect this today in the snapshot.

Regards,

Jeroen

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ceyhun kerti

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Jan 16, 2015, 8:44:07 AM1/16/15

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thanks for the quick reply.

That is good. btw. I can play with hearhbeat till next day. is it sent internally or shuold we send hearthbeat using api.

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Jeroen van Erp

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Jan 16, 2015, 9:00:57 AM1/16/15

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Hi Ceyhun,

It's as simple as:

ssh.getTransport().setHeartbeatInterval(5) // Sends a heartbeat every 5 seconds.

Regards,
Jeroen

ceyhun kerti

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Jan 16, 2015, 9:03:58 AM1/16/15

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thanks a lot.

i'll try that and look forward for the keepAlive

You've been very helpfull

ceyhun kerti

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Jan 20, 2015, 4:05:08 AM1/20/15

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Hi Jeroen, I see on git you've added KeepAlive thanks for the good work.

My question is;

I am using maven repo with gradle, how can i optain the latest build? Should i clone git repo and build it?

And i iam planing to use keepAlive like

ssh.getConnection().getKeepAlive().setKeepAliveInterval(60); //every 60sec

is that right ?

Thanks again.

On Fri, Jan 16, 2015 at 3:40 PM, Jeroen van Erp <jer...@javadude.nl> wrote:

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Jeroen van Erp

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Jan 20, 2015, 4:34:14 AM1/20/15

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Hi ceyhun,

I am currently working on releasing it. Expect that somewhere this week. For now you can clone and build a snapshot and use that.

You need to do two things, I've added a new keep-alive mechanism, next to the default heartbeat mechanism that was used. In order to enable it, you need to do the following:

Config config = new DefaultConfig();

config.setKeepAliveProvider(KeepAliveProvider.KEEP_ALIVE);

SshClient ssh = new SshClient(config);

ssh.getConnection().getKeepAlive().setKeepAliveInterval(60); //every 60sec

regards,

Jeroen

ceyhun kerti

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Jan 20, 2015, 7:43:56 AM1/20/15

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Hi,

I have changed my code like

Config config = new DefaultConfig();
config.setKeepAliveProvider(KeepAliveProvider.KEEP_ALIVE);

ssh = new SSHClient(config);
ssh.addHostKeyVerifier(new PromiscuousVerifier());
ssh.connect(getHost());
ssh.getConnection().getKeepAlive().setKeepAliveInterval(60); //every 60sec

authenticate();
session = ssh.startSession();
session.allocateDefaultPTY();

log.debug("Executing command : " + envVarString + " " + command);

and started to get following error :

[ERROR] 2015-01-20 14:39:30.982 [reader] n.s.sshj.transport.TransportImpl - Dying because - {}
net.schmizz.sshj.common.SSHException: Unexpected: SSH_MSG_UNIMPLEMENTED
	at net.schmizz.sshj.AbstractService.notifyUnimplemented(AbstractService.java:63) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]
	at net.schmizz.sshj.transport.TransportImpl.gotUnimplemented(TransportImpl.java:566) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]
	at net.schmizz.sshj.transport.TransportImpl.handle(TransportImpl.java:497) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]
	at net.schmizz.sshj.transport.Decoder.decode(Decoder.java:107) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]
	at net.schmizz.sshj.transport.Decoder.received(Decoder.java:175) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]
	at net.schmizz.sshj.transport.Reader.run(Reader.java:61) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]
[ERROR] 2015-01-20 14:39:30.984 [actorSystem-akka.actor.default-dispatcher-2] net.schmizz.concurrent.Promise - <<service accept>> woke to: net.schmizz.sshj.transport.TransportException: Unexpected: SSH_MSG_UNIMPLEMENTED

any suggestion ?

Thanks.

Jeroen van Erp

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Jan 20, 2015, 7:49:08 AM1/20/15

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Hi Ceyhun,

That's weird... Could you post more logging? Also debug logging from the ssh server?

Regards,
Jeroen

ceyhun kerti

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Jan 20, 2015, 10:32:53 AM1/20/15

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Hi below are the logs. I am also looking for possible solution if i find something i'll inform you.

Thanks in advance.

SSH server

------------------------------------------------------------------------------------------

debug1: sshd version OpenSSH_6.6.1, OpenSSL 1.0.1f 6 Jan 2014

debug1: key_parse_private2: missing begin marker

debug1: read PEM private key done: type RSA

debug1: private host key: #0 type 1 RSA

debug1: key_parse_private2: missing begin marker

debug1: read PEM private key done: type DSA

debug1: private host key: #1 type 2 DSA

debug1: key_parse_private2: missing begin marker

debug1: read PEM private key done: type ECDSA

debug1: private host key: #2 type 3 ECDSA

debug1: private host key: #3 type 4 ED25519

debug1: rexec_argv[0]='/usr/sbin/sshd'

debug1: rexec_argv[1]='-d'

Set /proc/self/oom_score_adj from 0 to -1000

debug1: Bind to port 22 on 0.0.0.0.

Server listening on 0.0.0.0 port 22.

debug1: Bind to port 22 on ::.

Server listening on :: port 22.

debug1: Server will not fork when running in debugging mode.

debug1: rexec start in 5 out 5 newsock 5 pipe -1 sock 8

debug1: inetd sockets after dupping: 3, 3

Connection from 127.0.0.1 port 37210 on 127.0.0.1 port 22

debug1: Client protocol version 2.0; client software version SSHJ_0_9_2

debug1: no match: SSHJ_0_9_2

debug1: Enabling compatibility mode for protocol 2.0

debug1: Local version string SSH-2.0-OpenSSH_6.6.1p1 Ubuntu-2ubuntu2

debug1: permanently_set_uid: 118/65534 [preauth]

debug1: list_hostkey_types: ssh-rsa,ssh-dss,ecdsa-sha2-nistp256,ssh-ed25519 [preauth]

debug1: SSH2_MSG_KEXINIT sent [preauth]

debug1: SSH2_MSG_KEXINIT received [preauth]

debug1: kex: client->server aes128-ctr hmac-sha1 none [preauth]

debug1: kex: server->client aes128-ctr hmac-sha1 none [preauth]

debug1: expecting SSH2_MSG_KEXDH_INIT [preauth]

debug1: SSH2_MSG_NEWKEYS sent [preauth]

debug1: expecting SSH2_MSG_NEWKEYS [preauth]

debug1: SSH2_MSG_NEWKEYS received [preauth]

debug1: KEX done [preauth]

dispatch_protocol_error: type 80 seq 3 [preauth]

Received disconnect from 127.0.0.1: 2: Unexpected: SSH_MSG_UNIMPLEMENTED [preauth]

debug1: do_cleanup [preauth]

debug1: do_cleanup

debug1: Killing privsep child 5693

Application

------------------------------------------------------------------------------------------

120/graph_20150120/TASK07_20150120 - Running task

[WARN ] 2015-01-20 17:20:32.539 [actorSystem-akka.actor.default-dispatcher-4] net.schmizz.sshj.DefaultConfig - Disabling high-strength ciphers: cipher strengths apparently limited by JCE policy

[ERROR] 2015-01-20 17:20:33.095 [reader] n.s.sshj.transport.TransportImpl - Dying because - {}

ceyhun kerti

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Jan 20, 2015, 10:43:08 AM1/20/15

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Hi,

I've reordered my code like

authenticate();
ssh.getConnection().getKeepAlive().setKeepAliveInterval(60); //every 60sec

so setKeepAlive comes after authenticate(). And everything is ok the exception is gone.

Next I'll test if keepAlive func. is working...

Jeroen van Erp

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Jan 20, 2015, 10:44:21 AM1/20/15

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I'll try it here too... Could you also post the debug logging from sshj?

Regards,

Jeroen

ceyhun kerti

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Jan 20, 2015, 10:45:11 AM1/20/15

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hmm how could i get the debug logging ?

Jeroen van Erp

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Jan 20, 2015, 10:49:53 AM1/20/15

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Change "logback.xml" to put the "net.schmizz" logger on "debug" level.

Something like

ceyhun kerti

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Jan 20, 2015, 11:03:15 AM1/20/15

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I've reverted the code and i got the logs.

btw. to expand the code more

what i do is

Config config = new DefaultConfig();
config.setKeepAliveProvider(KeepAliveProvider.KEEP_ALIVE);
ssh = new SSHClient(config);
ssh.addHostKeyVerifier(new PromiscuousVerifier());
ssh.connect(getHost());
ssh.getConnection().getKeepAlive().setKeepAliveInterval(60); //every 60sec
authenticate();
session = ssh.startSession();
session.allocateDefaultPTY();
log.debug("Executing command : " + envVarString + " " + command);

and uthenticate() is like

private void authenticate() throws UserAuthException, TransportException {

    final String password =

     if (StringUtils.hasText(password)) {
        --> i donot use uname/pass login so code never reaches here

        final String decryptedPassword = CryptoUtils.decrypt(password);
        ssh.authPassword(getUsername(), decryptedPassword);
    } else {
        ssh.authPublickey(getUsername());    ----> Actually  this section is executed
    }
}

net.schmizz.sshj.common.SSHException: Unexpected: SSH_MSG_UNIMPLEMENTED

at net.schmizz.sshj.AbstractService.notifyUnimplemented(AbstractService.java:63) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]

at net.schmizz.sshj.transport.TransportImpl.gotUnimplemented(TransportImpl.java:566) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]

at net.schmizz.sshj.transport.TransportImpl.handle(TransportImpl.java:497) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]

at net.schmizz.sshj.transport.Decoder.decode(Decoder.java:107) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]

at net.schmizz.sshj.transport.Decoder.received(Decoder.java:175) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]

at net.schmizz.sshj.transport.Reader.run(Reader.java:61) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]

[INFO ] 2015-01-20 17:56:40.512 [reader] n.s.sshj.transport.TransportImpl - Disconnected - PROTOCOL_ERROR

[DEBUG] 2015-01-20 17:56:40.515 [reader] n.s.sshj.transport.KeyExchanger - Got notified of net.schmizz.sshj.common.SSHException: [PROTOCOL_ERROR] Unexpected: SSH_MSG_UNIMPLEMENTED

[DEBUG] 2015-01-20 17:56:40.516 [reader] n.s.s.t.TransportImpl$NullService - Notified of net.schmizz.sshj.common.SSHException: [PROTOCOL_ERROR] Unexpected: SSH_MSG_UNIMPLEMENTED

[DEBUG] 2015-01-20 17:56:40.517 [reader] n.s.sshj.transport.TransportImpl - Setting active service to null-service

[DEBUG] 2015-01-20 17:56:40.518 [reader] n.s.sshj.transport.TransportImpl - Sending SSH_MSG_DISCONNECT: reason=[PROTOCOL_ERROR], msg=[Unexpected: SSH_MSG_UNIMPLEMENTED]

[DEBUG] 2015-01-20 17:56:40.526 [reader] net.schmizz.concurrent.Promise - Setting <<transport close>> to `SOME`

[DEBUG] 2015-01-20 17:56:40.528 [reader] net.schmizz.sshj.transport.Reader - Stopping

[DEBUG] 2015-01-20 17:56:40.529 [actorSystem-akka.actor.default-dispatcher-7] net.schmizz.concurrent.Promise - Setting <<service accept>> to `null`

----- End of the daemon log -----

ceyhun kerti

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Jan 20, 2015, 11:07:12 AM1/20/15

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More logs :

ntu-2ubuntu2

[DEBUG] 2015-01-20 18:05:11.237 [actorSystem-akka.actor.default-dispatcher-2] net.schmizz.concurrent.Promise - Setting <<kex done>> to `null`

[DEBUG] 2015-01-20 18:05:11.239 [actorSystem-akka.actor.default-dispatcher-2] n.s.sshj.transport.KeyExchanger - Sending SSH_MSG_KEXINIT

[DEBUG] 2015-01-20 18:05:11.243 [reader] n.s.sshj.transport.KeyExchanger - Received SSH_MSG_KEXINIT

[DEBUG] 2015-01-20 18:05:11.245 [reader] net.schmizz.concurrent.Promise - Awaiting <<kexinit sent>>

[DEBUG] 2015-01-20 18:05:11.247 [actorSystem-akka.actor.default-dispatcher-2] net.schmizz.concurrent.Promise - Setting <<kexinit sent>> to `SOME`

[DEBUG] 2015-01-20 18:05:11.248 [actorSystem-akka.actor.default-dispatcher-2] net.schmizz.concurrent.Promise - Awaiting <<kex done>>

[DEBUG] 2015-01-20 18:05:11.249 [reader] n.s.sshj.transport.KeyExchanger - Negotiated algorithms: [ kex=diffie-hellman-group14-sha1; sig=ecdsa-sha2-nistp256; c2sCipher=aes128-ctr; s2cCipher=aes128-ctr; c2sMAC=hmac-sha1; s2cMAC=hmac-sha1; c2sComp=none; s2cComp=none ]

[DEBUG] 2015-01-20 18:05:11.330 [reader] net.schmizz.sshj.transport.kex.DHG14 - Sending SSH_MSG_KEXDH_INIT

[DEBUG] 2015-01-20 18:05:11.334 [reader] n.s.sshj.transport.KeyExchanger - Received kex followup data

[DEBUG] 2015-01-20 18:05:11.334 [reader] net.schmizz.sshj.transport.kex.DHG14 - Received SSH_MSG_KEXDH_REPLY

[DEBUG] 2015-01-20 18:05:11.335 [reader] net.schmizz.sshj.common.KeyType$3 - Key algo: ecdsa-sha2-nistp256, Key curve: nistp256, Key Len: 65, 0x04: 4

x: [-4, 115, 99, 73, -40, 126, 125, 62, -112, 68, 15, 24, -79, 118, -25, -128, -7, 119, 106, 30, 52, 57, -5, 37, -105, -55, 103, -64, 34, 45, 89, -42]

y: [71, 74, 120, 96, 121, -15, -81, -4, -23, -13, 35, 120, -94, -51, -84, -89, -73, -89, 54, 44, 118, -48, 13, -50, -97, -18, -3, 45, -37, 55, -78, -21]

[DEBUG] 2015-01-20 18:05:11.739 [actorSystem-akka.actor.default-dispatcher-3] akka://actorSystem/user/periodicPlanMaker - Checking for new [PlanInstance]s to set

[DEBUG] 2015-01-20 18:05:11.740 [actorSystem-akka.actor.default-dispatcher-3] akka://actorSystem/user/periodicPlanMaker/planInstanceSetter - Checking for new [PlanInstance]s to set

[DEBUG] 2015-01-20 18:05:11.745 [reader] n.s.sshj.transport.KeyExchanger - Trying to verify host key with net.schmizz.sshj.transport.verification.PromiscuousVerifier@6c23e17

[DEBUG] 2015-01-20 18:05:11.746 [reader] n.s.sshj.transport.KeyExchanger - Sending SSH_MSG_NEWKEYS

[DEBUG] 2015-01-20 18:05:11.747 [reader] n.s.sshj.transport.KeyExchanger - Received SSH_MSG_NEWKEYS

[DEBUG] 2015-01-20 18:05:11.756 [reader] net.schmizz.concurrent.Promise - Setting <<kexinit sent>> to `null`

[DEBUG] 2015-01-20 18:05:11.757 [reader] net.schmizz.concurrent.Promise - Setting <<kex done>> to `SOME`

[DEBUG] 2015-01-20 18:05:11.758 [actorSystem-akka.actor.default-dispatcher-2] net.schmizz.sshj.SSHClient - Key exchange took 0.521 seconds

[DEBUG] 2015-01-20 18:05:11.760 [actorSystem-akka.actor.default-dispatcher-2] net.schmizz.sshj.SSHClient - Attempting to load key from: /home/ceyhun/.ssh/id_rsa

[DEBUG] 2015-01-20 18:05:11.763 [keep-alive] n.schmizz.keepalive.KeepAliveRunner - Starting KeepAliveRunner, sending keep-alive every 60 seconds

[DEBUG] 2015-01-20 18:05:11.764 [keep-alive] n.schmizz.keepalive.KeepAliveRunner - Sending keep-alive since 60 seconds elapsed

[DEBUG] 2015-01-20 18:05:11.765 [keep-alive] n.s.sshj.connection.ConnectionImpl - Making global request for `keep...@openssh.com`

[DEBUG] 2015-01-20 18:05:11.805 [reader] n.s.sshj.transport.TransportImpl - Received SSH_MSG_UNIMPLEMENTED #3

[DEBUG] 2015-01-20 18:05:11.820 [actorSystem-akka.actor.default-dispatcher-2] net.schmizz.sshj.SSHClient - Attempting to load key from: /home/ceyhun/.ssh/id_dsa

[INFO ] 2015-01-20 18:05:11.821 [actorSystem-akka.actor.default-dispatcher-2] net.schmizz.sshj.SSHClient - Could not load keys from /home/ceyhun/.ssh/id_dsa due to: /home/ceyhun/.ssh/id_dsa (No such file or directory)

[ERROR] 2015-01-20 18:05:11.822 [reader] n.s.sshj.transport.TransportImpl - Dying because - {}

net.schmizz.sshj.common.SSHException: Unexpected: SSH_MSG_UNIMPLEMENTED

at net.schmizz.sshj.AbstractService.notifyUnimplemented(AbstractService.java:63) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]

at net.schmizz.sshj.transport.TransportImpl.gotUnimplemented(TransportImpl.java:566) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]

at net.schmizz.sshj.transport.TransportImpl.handle(TransportImpl.java:497) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]

at net.schmizz.sshj.transport.Decoder.decode(Decoder.java:107) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]

at net.schmizz.sshj.transport.Decoder.received(Decoder.java:175) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]

at net.schmizz.sshj.transport.Reader.run(Reader.java:61) ~[sshj-master-0.11.0-SNAPSHOT.jar:na]

[INFO ] 2015-01-20 18:05:11.831 [reader] n.s.sshj.transport.TransportImpl - Disconnected - PROTOCOL_ERROR

[DEBUG] 2015-01-20 18:05:11.833 [reader] n.s.sshj.transport.KeyExchanger - Got notified of net.schmizz.sshj.common.SSHException: [PROTOCOL_ERROR] Unexpected: SSH_MSG_UNIMPLEMENTED

[DEBUG] 2015-01-20 18:05:11.834 [reader] n.s.s.t.TransportImpl$NullService - Notified of net.schmizz.sshj.common.SSHException: [PROTOCOL_ERROR] Unexpected: SSH_MSG_UNIMPLEMENTED

[DEBUG] 2015-01-20 18:05:11.836 [reader] n.s.sshj.transport.TransportImpl - Setting active service to null-service

[DEBUG] 2015-01-20 18:05:11.837 [reader] n.s.sshj.transport.TransportImpl - Sending SSH_MSG_DISCONNECT: reason=[PROTOCOL_ERROR], msg=[Unexpected: SSH_MSG_UNIMPLEMENTED]

The message received from the daemon indicates that the daemon has disappeared.

Build request sent: BuildAndStop{id=d518bf06-34c5-4f30-a0e0-4c8afc3b6960.1, currentDir=/home/ceyhun/projects/sch}

Attempting to read last messages from the daemon log...

Daemon pid: 7163

log file: /home/ceyhun/.gradle/daemon/1.9/daemon-7163.out.log

----- Last 20 lines from daemon log file - daemon-7163.out.log -----