Open port on GCE but still closed - google-compute-engine

I created a new firewall rule open 8332/8333/18332/18332 tcp ports but when i run nmap i can't see these ports.
It has an service running on 8332 but for me still closed.
External IP: 34.95.163.181
Cheers.

Related

LocalServer - 2/3 services Running WAMP - MySQL is not Running [FIXED]

I recently ran into a problem that mysqld service wasn't running.
I checked the MySQL's wamp log and got the following messages:
[ERROR] Can't start server: Bind on TCP/IP port: No such file or directory
[ERROR] Do you already have another mysqld server running on port: 3306 ?
So I ran it and realized that my TCP port 3306 was already running with another mysqld.exe process
netstat -ano|find "3306"
TCP 0.0.0.0:3306 0.0.0.0:0 LISTENING 4576
TCP 0.0.0.0:33060 0.0.0.0:0 LISTENING 4576
TCP [::]:3306 [::]:0 LISTENING 4576
TCP [::]:33060 [::]:0 LISTENING 4576
after that I went to Task Manager and found the 4576 PID which was the other mysqld.exe running. So I finished the task and restarted my WAMP server, and all services went smoothly.
The problem probably occurred because I've got two wamp servers installed, don't ask me why... Hope I can help someone with this same problem.

Google Dataproc - Unable to connect via SSH

I installed a Cloud Datalab notebook on a Cloud Dataproc cluster following the instructions listed in the official documentation
After creating the cluster, I then created a SSH tunnel to the master node in the Cloud Shell and connected to the cluster interface using the Cloud Shell. Instructions. I could access the Jupyter notebooks after this. I used the -v verbose option to see the SSH connection logs:
gcloud compute ssh cluster-datalab-m --project=abcxyz-123 --zone us-west1-a \
-- -v -4 -N -L 8080:cluster-datalab-m:8080
But after some time, I got a popup saying "A connection to the notebook server could not be established. The notebook will continue trying to reconnect. Check your network connection or notebook server configuration." and my cluster stopped responding to any commands.
When I looked at the SSH output on the Cloud Shell, I saw that multiple channels were being requested at this point.
A preview of SSH logs just during the break point:
debug1: channel 1: new [direct-tcpip]
debug1: Connection to port 8080 forwarding to cluster-datalab-m port 8080 requested.
debug1: channel 2: new [direct-tcpip]
debug1: channel 1: free: direct-tcpip: listening port 8080 for cluster-datalab-m port 8080, connect from 127.0.0.1 port 52832 to 127.0.0.1 port 8080, nchannels 3
debug1: channel 2: free: direct-tcpip: listening port 8080 for cluster-datalab-m port 8080, connect from 127.0.0.1 port 52833 to 127.0.0.1 port 8080, nchannels 2
debug1: Connection to port 8080 forwarding to cluster-datalab-m port 8080 requested.
debug1: channel 1: new [direct-tcpip]
debug1: Connection to port 8080 forwarding to cluster-datalab-m port 8080 requested.
debug1: channel 2: new [direct-tcpip]
debug1: channel 2: free: direct-tcpip: listening port 8080 for cluster-datalab-m port 8080, connect from 127.0.0.1 port 52837 to 127.0.0.1 port 8080, nchannels 3
debug1: Connection to port 8080 forwarding to cluster-datalab-m port 8080 requested.
debug1: channel 2: new [direct-tcpip]
debug1: Connection to port 8080 forwarding to cluster-datalab-m port 8080 requested.
debug1: channel 3: new [direct-tcpip]
debug1: Connection to port 8080 forwarding to cluster-datalab-m port 8080 requested.
debug1: channel 4: new [direct-tcpip]
debug1: Connection to port 8080 forwarding to cluster-datalab-m port 8080 requested.
debug1: channel 5: new [direct-tcpip]
debug1: Connection to port 8080 forwarding to cluster-datalab-m port 8080 requested.
debug1: channel 6: new [direct-tcpip]
debug1: Connection to port 8080 forwarding to cluster-datalab-m port 8080 requested.
I closed this SSH connection manually and then tried to SSH into the master node by clicking the SSH button on the Compute Engine console but even that was taking lot of time and didn't complete successfully.
I looked at this stackoverflow question but I couldn't find any /etc/sshguard folder in the master node so I don't think that is the issue for my case. The master node was running Debian 8.10.
Is there any way to ensure that the SSH connection (and the Jupyter notebook) works continuously?
We've updated the documentation at cluster web interfaces. Using cloud shell works for Datalab, but not Jupyter. Cloud Shell Preview only supports HTTP, but Jupyter uses websockets.
Instead, you should follow the instructions for setting up a SOCKS proxy and pointing Chrome at it. There's a handy bash script called launch-jupyter-interface.sh that does that for you. You'll just need to modify it to point to your Chrome installation.
The Jupyter tutorial also mentions using that script.

Connecting to MariaDb on Windows through putty ssh tunnel

Background: I've been connecting to MySql from Windows to an Ubuntu VM through putty's ssh tunnel for years now, and it's worked great.
2 weeks ago I started up a new Ubuntu 16.06 amd64 VM, put the latest MariaDb on it, and everything worked as before. Workbench worked, and my code was able to connect through the tunnel as well.
Last week, the connection somehow became unstable. It would not connect anymore, and timeouts would occur 100% of the time until it mysteriously started working again. Even now, at the beginning of writing this question, it was not working. Now it is. It has sometimes not worked when ufw was disabled completely. Does anyone know what is going on? Are there timeouts or cooldowns on the various pieces that I'm not aware of? I've restarted the service countless times, and the VM many times as well.
Configuration:
my.cnf:
bind-address = 127.0.0.1
ufw:
Status: active
Logging: on (low)
Default: deny (incoming), allow (outgoing), disabled (routed)
New profiles: skip
To Action From
-- ------ ----
80/tcp ALLOW IN Anywhere
443/tcp ALLOW IN Anywhere
22/tcp ALLOW IN Anywhere
3306 on lo ALLOW IN Anywhere
127.0.0.1 3306/tcp ALLOW IN Anywhere
80/tcp (v6) ALLOW IN Anywhere (v6)
443/tcp (v6) ALLOW IN Anywhere (v6)
22/tcp (v6) ALLOW IN Anywhere (v6)
3306 (v6) on lo ALLOW IN Anywhere (v6)

Zabbix JMX Tomcat monitoring

I have been trying to setup Zabbix to monitor my 2 tomcat servers on 2 different Amazon EC2 machines, but in vain.
The Z on the host is green, however te JMX is red with these errors
- ZBX_TCP_READ() failed: [4] Interrupted system call
- Someother error [111] connection refused
and many such errors, one after another, in the sense I resolve an error to see one more new error popping up.
These are some assumptions
All the machines run Ubuntu 12.10 and later
Server's IP address: 66.55.12.120 (Runs Zabbix server v2.2.4 (revision 46772) (23 June 2014) )
Agent's IP address: 87.52.45.198 ( Runs Zabbix agent v2.2.2 (revision 42525) (12 February 2014) )
My local machine's IP address: 76.89.54.111
Here is what I've done so far.
On Server Side:
1) Installed Zabbix_server using sudo apt-get install zabbix-server-mysql.
2) The GUI, mysql database all have been installed and configured.
3) The following are the only 3 changes that I've made in the file /etc/zabbix/zabbix_server.conf
...
JavaGateway=localhost
JavaGatewayPort=10052
StartJavaPollers=5
...
4) The Zabbix Java gateway was installed using sudo apt-get install zabbix-java-gateway.
5) The following are the only 3 changes that I've made in the file
/etc/zabbix/zabbix_java_gateway.conf
...
LISTEN_IP="127.0.0.1"
LISTEN_PORT=10052
START_POLLERS=5
...
On Client Side:
1) Installed Zabbix Client using
sudo apt-get install zabbix-agent
2) The following are the only 3 changes that I've made in the file
/etc/zabbix/zabbix_agentd.conf
...
Server=66.55.12.120
StartAgents=5
ServerActive=66.55.12.120:10051
Hostname=Security-test-JMX-EC2
... <br />
3) The Hostname is the same as the one that is mentioned while creating the Host on the GUI.
I believe that there are some issues with the IP and ports. So, here are the outbound rules for both the machines as obtained from Amazon EC2 Security Groups for the machines
OUTBOUND RULES for SERVER SECURITY GROUP:
Type Protocol Port Source Reasoning
Custom- TCP 8080 0.0.0.0/0
TCP Rule
All ICMP All N/A 0.0.0.0/0
Custom- TCP 10052 27.52.52.128/32 For access from Agent
TCP Rule
Custom- TCP 8081 76.84.120.130/32 To access Zabbix GUI from-
TCP Rule -my local machine's web browser
Custom- TCP 10051 27.52.52.128/32 As the agent responds to-
TCP Rule -the server on Port 10051TCP Rule-
-Must allow inbound communications-
- from the agent.
Custom- TCP 11000 27.52.52.128/32 The agent's JMX reporting-
TCP Rule -happens on port 11000(not on 12345).
OUTBOUND RULES for CLIENT SECURITY GROUP:
Type Protocol Port Source
HTTPS TCP 443 0.0.0.0/0
Custom- TCP 10050 66.55.12.120/32
TCP Rule
Custom- TCP 10052 66.55.12.120/32
TCP Rule
Custom- TCP 11000 66.55.12.120/32
TCP Rule
HTTP TCP 80 76.89.54.111/32
Custom- TCP 8080 76.89.54.111/32
TCP Rule
Custom- TCP 8443 76.89.54.111/32
TCP Rule
What am I missing? Please guide me.
Any help is appreciated.
Thanks
Goutham
If you can, then run VisualVm (probably using a tunneled X session) on the zabbix host, and see if you can connect to the target JVM with that. If you can't connect from that, you won't be able to connect from Zabbix.
Try with the following CATALINA_OPTS, replacing with the IP on the target that you want JMX to listen on:
export CATALINA_OPTS="-Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.port=9010 -Dcom.sun.management.jmxremote.local.only=falseom.sun.management.jmxremote.authenticate=false -Dcom.sun.management.jmxremote.ssl=false -Djava.rmi.server.hostname=<LOCAL_IP>"
This will disable all JMX security so be aware!
Once you hopefully get it to connect, the "Tomcat JMX" items in Zabbix are also all incorrect! e.g.
Incorrect Zabbix default:
jmx["Catalina:type=GlobalRequestProcessor,name=http-8080",bytesReceived]
Correct entry:
jmx["Catalina:type=ThreadPool,name=\"http-bio-8080\"", bytesReceived]
Note the escaped quotes and incorrect thread name. Add the Mbeans plugin to VisualVM, and use that to browse the MBeans on the target VM, and check the Zabbix names.
It does work eventually, but is a real pain to setup. Zabbix is however one of the few open source monitoring tools that supports JMX at all!
By default, JMX does not work very well with firewalls. You might find related bug reports on Zabbix tracker useful: ZBX-5326 and ZBX-6815. The first one contains a workaround for Tomcat which might work for you.
#gvatreya wrote:
Server: (Runs Zabbix server)
Agent: (Runs Zabbix agent)
It looks like you have to start Zabbix Java gateway as well on host where it is installed (it is a daemon/service).
I configured as follows:
Server: (Runs Zabbix server, Zabbix Java gateway)
Agent: (Runs Zabbix agent)
I think it is possible to install it on a dedicated host.
Have you tried adding -Djava.net.preferIPv4Stack=true to the VM options?
to make it work add next java_opts to your tomcat startup script
-Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.authenticate=false
-Dcom.sun.management.jmxremote.port=2345
-Dcom.sun.management.jmxremote.rmi.port=12345
-Djava.rmi.server.hostname=<tomcat_hostname>

Xampp; Apache Port 80 Busy

I am having Port Problem.
Whenever I start Apache then it give me this error:
Busy - Apache Started [port 80]
And When i start Mysql then Folowing Error Appears:
Busy - ERROR: Mysql service not started [-1]
Please Anyone tell me that how to resolve this problem.
Waiting for Replies.
Thanks in Advance
Open cports.exe (http://www.nirsoft.net/utils/cports.html), find in the column Local Port the port 80. Thus, you will know which program uses this port and you will be able to kill it.
For most people, port 80 is occupied by Skype by default. Simply uninstall Skype and port 80 will be freed. Apache should then work.
Try to run this below command in cmd prompt
netstat -ano|find "port no"
Eg:
netstat -ano|find "3306"
TCP 0.0.0.0:3306 0.0.0.0:0 LISTENING 5164
TCP [::]:3306 [::]:0 LISTENING 5164
You could even use the pid number and check in windows task manager who is utilizing these pid so that you would come to know the exact process name
Please provide error log file if possible.
Major issue comes if you are using skype . Just change the connection port no and restart skype and try to start apache
You should search then you ask question because this question has been asked. You need to go to C:\xampp\apache\conf edit httpd.conf file and change
Listen 80
to
Listen 8081
or another number then you restart apache.
other links
Configure apache to listen on port other than 80
Edit the httpd file
#Listen 12.34.56.78:80
Listen 80
to something like this
#Listen 12.34.56.78:80
Listen 8080
Just make sure you use any port other than 80.
Check if any instances of mysqld.exe is running from task manager. If so kill it and start it from xampp control panel.
If you have skype running on your local computer it uses port 80 also. So port 80 can not allocate for MySQL. The solution is to stop running on skype and then start your xampp server. If it is also not working just try to uninstall skype and then again install your xampp server. This time probably can run MySQL.