I've been using Mongo for a while now, and I never had any kind of errors. But today, I tried running the mongo command in my terminal and I got the following error:
Error connecting to 127.0.0.1:27017 :: caused by :: No connection could be made because the target machine actively refused it. :
I have my PATH variable for Mongo properly configured in my environment variables as follows:
C:\Program Files\MongoDB\Server\4.4\bin
so I doubt that is the issue. I remember going through my task manager yesterday and I accidentally terminated a program running in the background related to Mongo, but I can't seem to remember exactly what it was called, and I really think that that's the root of my problem, because before having terminated that Mongo program in my task manager I had never ran across this connection problem before.
By terminating a program in the background, I'm going to assume you didn't just end process, otherwise a simple computer restart would fix your issue. And in some cases, that same program would've relaunched when you launched MongoDB. But if you disabled a service and need to find which service needs to be running to be able to connect to your MongDB then I would suggest going through your Windows Services list and seeing which ones you disabled and looking one relating to TCP or SNMP.
This is because MongoDB Wire Protocol is a simple socket-based, request-response style protocol. You communicate with the database server through a regular TCP/IP socket and since you can't remember which one you "terminated" and any number of services related to networking can cause a dependency to be absent, I can't be more specific in helping you determine which one you need to turn back on and you'll have to do it through trial and error but I can at least offer you some guidance, hopefully.
Specifically you can either
Run system configuration using
msconfig
In a run box, navigating to the Services tab, order the list by Date Disabled to find the service that was disabled which correlates with when you when snooping through task manager, or
Run Task manager and navigate to the Services Tab, then Open Services, and order them by Status or by Name, and look for any service that includes TCP/IP, COM+, Port direction, etc. to see which one is disabled and change the configuration from anything but Disabled and then stat it manually and run MongDB again.
It's about as specific as I can get without knowing anything more than you terminated some program running in the background but I hope it helps.
The background process (daemon) for MongoDB is called 'mongod'. It's an executable in your bin directory inside your mongodb installation. You can just execute it in the terminal.
Run:
C:\Program Files\MongoDB\Server\4.4\bin\mongod.exe
Related
I am using ORACLE database in a windows environment and running a JSP/servlet web application in tomcat. After I do some operations with the application it gives me the following error.
ORA-12518, TNS: listener could not hand off client connection
can any one help me to identify the reason for this problem and propose me a solution?
The solution to this question is to increase the number of processes :
1. Open command prompt
2. sqlplus / as sysdba; //login sysdba user
3. startup force;
4. show parameter processes; // This shows 150(some default) processes allocated, then increase the count to 800
5. alter system set processes=800 scope=spfile;
As Tried and tested.
In my case I found that it is because I haven't closed the database connections properly in my application. Too many connections are open and Oracle can not make more connections. This is a resource limitation. Later when I check with oracle forum I could see some reasons that have mentioned there about this problem. Some of them are.
In most cases this happens due to a network problem.
Your server is probably running out of memory and need to swap memory to disk.One cause can be an Oracle process consuming too much memory.
if it is the second one, please verify large_pool_size or check dispatcher were enough for all connection.
You can refer bellow link for further details.
https://community.oracle.com/message/1874842#1874842
I ran across the same problem, in my case it was a new install of the Oracle client on a new desktop that was giving the error, other clients were working so I knew it wouldn't be a fix to the database configuration. tnsping worked properly but sqlplus failed with the ora-12518 listener error.
I had the tnsnames.ora entry with a SID instead of a service_name, then once I fixed that, still the same error and found I had the wrong service_name as well. Once I fixed that, the error went away.
If from one day to another the issue shows for no apparent reasons, add these following lines at the bottom of the listner.ora file. If your oracle_home environment variable is set like this:
(ORACLE_HOME = C:\oracle11\app\oracle\product\11.2.0\server)
The lines to add are:
ADR_BASE_LISTENER = C:\oracle11\app\oracle\
DIRECT_HANDOFF_TTC_LISTENER=OFF
I had the same problem when executing queries in my application. I'm using Oracle client with Ruby on Rails.
The problem started when I accidentally started several connections with the DB and didn't close them.
When I fixed this, everything started to work fine again.
Hope this helps another one with the same problem.
I experienced the same error after upgrading to Windows 10. I solved it by starting services for Oracle which are stopped.
Start all the services as shown in the following image:
I had the same issue. After restarting all Oracle services it worked again.
same problem encountered for me.
And from oracle server listener log, can see more information.
and I found that the SERVICE_NAME is not match the tnsnames.ora configured Service name. so I changed the application's data source configuration from SID value to Service_NAME value and it fixed.
23-MAY-2019 02:44:21 * (CONNECT_DATA=(CID=(PROGRAM=JDBC Thin Client)(HOST=__jdbc__)(USER=XXXXXX$))(SERVICE_NAME=orclaic)) * (ADDRESS=(PROTOCOL=tcp)(HOST=::1)(PORT=50818)) * establish * orclaic * 12518
TNS-12518: TNS:listener could not hand off client connection
TNS-12560: TNS:protocol adapter error
TNS-00530: Protocol adapter error
64-bit Windows Error: 203: Unknown error
I had the same issue in real time application and the issue gone by itself next day. upon checking, it was found that server ran out of memory due to additional processes running.
So in my case, the reason was server run out of memory
first of all
check the listener log
check the show parameter processes vs select count(*) from v$processes;
increase the process, it may require SGA increase
;
My Sql developer was working fine from long time, suddenly from yesterday when i am trying to reconnect it is giving me following error:-
Status : Failure -Test failed: IO Error: Got minus one from a read call, connect lapse 62991 ms., Authentication lapse 0 ms.
Things I tried to solve the issue:-
Made corresponding changes in sqlnet.ora , listener.ora and tnsnames.ora files
Checked is there are too many open connections to the database service.
Restarted ORACLE service and listener
Firewall related changes
Reinstalled ORACLE
In my case the issue, it is due to a malware. Whenever i am trying to connect to DB port, it was automatically getting changed by malware.
You can also identify the problem by using lsnrctl status command, for further information. You can also see the log file of listener.
Run a full scan on your machine and restart listener, hope that helps.
I have setup the apache cloudstack on CentOS 6.8 machine following quick installation guide. The management server and KVM are setup on the same machine. The management server is running without problems. I was able to add zone, pod, cluster, primary and secondary storage from the web interface. But when I tried to add an instance it is not showing any templates in the second stage as you can see in the screenshot
However, I am able to see two templates under Templates link in web UI.
But when I select the template and navigate to Zone tab, I see Timeout waiting for response from storage host and Ready field shows no.
When I check the management server logs, it seems there is an error when cloudstack tries to mount secondary storage for use. The below segment from cloudstack-management.log file describes this error.
2017-03-09 23:26:43,207 DEBUG [c.c.a.t.Request] (AgentManager-Handler-
14:null) (logid:) Seq 2-7686800138991304712: Processing: { Ans: , MgmtId:
279278805450918, via: 2, Ver: v1, Flags: 10, [{"com.cloud.agent.api.Answer":
{"result":false,"details":"com.cloud.utils.exception.CloudRuntimeException:
GetRootDir for nfs://172.16.10.2/export/secondary failed due to
com.cloud.utils.exception.CloudRuntimeException: Unable to mount
172.16.10.2:/export/secondary at /mnt/SecStorage/6e26529d-c659-3053-8acb-
817a77b6cfc6 due to mount.nfs: Connection timed out\n\tat
org.apache.cloudstack.storage.resource.NfsSecondaryStorageResource.getRootDir(Nf
sSecondaryStorageResource.java:2080)\n\tat
org.apache.cloudstack.storage.resource.NfsSecondaryStorageResource.execute(NfsSe
condaryStorageResource.java:1829)\n\tat
org.apache.cloudstack.storage.resource.NfsSecondaryStorageResource.executeReques
t(NfsSecondaryStorageResource.java:265)\n\tat
com.cloud.agent.Agent.processRequest(Agent.java:525)\n\tat
com.cloud.agent.Agent$AgentRequestHandler.doTask(Agent.java:833)\n\tat
com.cloud.utils.nio.Task.call(Task.java:83)\n\tat
com.cloud.utils.nio.Task.call(Task.java:29)\n\tat
java.util.concurrent.FutureTask.run(FutureTask.java:262)\n\tat
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)\
n\tat
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)\
n\tat java.lang.Thread.run(Thread.java:745)\n","wait":0}}] }
Can anyone please guide me how to resolve this issue? I have been trying to figure it out for some hours now and don't know how to proceed further.
Edit 1: Please note that my LAN address was 10.103.72.50 which I assume is not /24 address. I tried to give CentOs a static IP by making the following settings in ifcg-eth0 file
DEVICE=eth0
HWADDR=52:54:00:B9:A6:C0
NM_CONTROLLED=no
ONBOOT=yes
BOOTPROTO=none
IPADDR=172.16.10.2
NETMASK=255.255.255.0
GATEWAY=172.16.10.1
DNS1=8.8.8.8
DNS2=8.8.4.4
But doing this would stop my internet. As a workaround, I reverted these changes and installed all the packages first. Then I changed the IP to static by the same configuration settings as above and ran the cloudstack management. Everything worked fine untill I bumped into this template thing. Please help me figure out what might have went wrong
I know I'm late, but for people trying out in the future, here it goes:
I hope you have successfully added a host as mentioned in Quick Install Guide before you changed your IP to static as it autoconfigures VLANs for different traffic and creates two bridges - generally with names 'cloud' or 'cloudbr'. Cloudstack uses the Secondary Storage System VM for doing all the storage-related operations in each Zone and Cluster. What seems to be the problem is that secondary storage system vm (SSVM) is not able to communicate with the management server at port 8250. If not, try manually mounting the NFS server's mount points in the SSVM shell. You can ssh into the SSVM using the below command:
ssh -i /var/cloudstack/management/.ssh/id_rsa -p 3922 root#<Private or Link local Ip address of SSVM>
I suggest you run the /usr/local/cloud/systemvm/ssvm-check.sh after doing ssh into the secondary storage system VM (assuming it is running) and has it's private, public and link local IP address. If that doesn't help you much, take a look at the secondary storage troubleshooting docs at Cloudstack.
I would further recommend, if anyone in future runs into similar issues, check if the SSVM is running and is in "Up" state in the System VMs section of Infrastructure tab and that you are able to open up a console session of it from the browser. If that is working go on to run the ssvm-check.sh script mentioned above which systematically checks each and every point of operation that SSVM executes. Even if console session cannot be opened up, you can still ssh using the link local IP address of SSVM which can be accessed by opening up details of SSVM and than execute the script. If it says, it cannot communicate with Management Server at port 8250, I recommend you check the iptables rules of management server and make sure all traffic is allowed at port 8250. A custom command to check the same is nc -v <mngmnt-server-ip> 8250. You can do a simple search and learn how to add port 8250 in your iptables rules if that is not opened. Next, you mentioned you used CentOS 6.8, so it probably uses older versions of nfs, so execute exportfs -a in your NFS server to make sure all the NFS shares are properly exported and there are no errors. I would recommend that you wait for the downloading status of CentOS 5.5 no GUI kvm template to be complete and its Ready status shown as 'Yes' before you start importing your own templates and ISOs to execute on VMs. Finally, if your ssvm-check.sh script shows everything is good and the download still does not start, you can run the command: service cloud restart and actually check if the service has gotten a PID using service cloud status as the older versions of system vm templates sometimes need us to manually start the cloud service using service cloud start even after the restart command. Restarting the cloud service in SSVM triggers the restart of downloading of all remaining templates and ISOs. Side note: the system VMs uses a Debian kernel if you want to do some more troubleshooting. Hope this helps.
I can't figure this one out. I can't connect to a server using MySQL Workbench, I tried any kind of connection methods. The error message I get is
Failed to Connect to MySQL at AT 127.0.0.1:3306 with user root
Invalid for this platform protocol requested(MYSQL_PROTOCOL_SOCKET)
I ran into the same problem, in my case I originally created the connection with the "Local Socket/Pipe" option selected in the "Connection Method" drop down. Trying to switch back to "Standard (TCP/IP)" did not work and caused the error mentioned by OP. I had to delete the connection and start over by selection "Standard (TCP/IP)" from the start. The connection was successful after that.
To solve this problem you must check the "Others" field in Advanced tab
If you had the connection stored with a socket option you will find a "socket=." (or anything similar)
Delete it
e.g. http://prntscr.com/k63pua
This is a very unusal error message which I haven't seen before, especially on Windows. It has probably to do with how the server is installed. As a newbie it would definitely be the best choice to use the Windows Installer for all required parts. This will install the server properly too.
By using xampp you are on your own to check whether a server is installed and running as a service, as well as the proper configuration. For troubleshooting watch my video on Youtube where I tried to explain most common pitfalls for beginners.
Note: you can open the connection without actually being connected. In that case MySQL Workbench allows to do all those things that don't require a valid server connection, e.g. log file viewing, config file editing, service start/stop etc. Use this to check your server's configuration. Make sure it accepts TCP/IP connections (there's also a short section in the video about this).
Update:
Downvoter, please add a comment why you think my answer is bad.
Re-reading the error message I got another idea: could it be that you used local socket/named pipe for the connection? If so try with normal TCP/IP.
in Solaris 10, when server restart, the backup daemon (tina_daemon) does not work properly when calling for another executable to shutdown the application services.
however, when manually restart the backup daemon, the calling for the executable works fine.
I found the following lines in the log-file:
8|9|tina_daemon|780|1|3|1373964994|1373964994|10739|tina_daemon_1|<host name deleted>|~|root|~|backup_poc_tina|backup-poc|Event handler daemon started|0|~|~|~|~|~|~|
8|9|tina_daemon|880|256|3|1373964994|1373964994|10739|tina_daemon_1|<host name deleted>|~|root|~|backup_poc_tina|backup-poc|Service opened, host "<host name deleted>", Time Navigator Enterprise Edition Version 4.2.8.8 P4680|0|~|~|~|~|~|~|
8|14|TNUnixSocketImpl::initNetServiceTcp|11|1|1|1373965001|1373965001|10963|tina_daemon_1|<host name deleted>|~|root|~|backup_poc_tina|backup-poc|Unable to bind 5 socket, retos=125 "Address already in use"|0|~|~|~|~|~|~|
8|14|vos_init_net_service_tcp|1|1|4|1373965001|1373965001|10963|tina_daemon_1|<host name deleted>|~|root|~|backup_poc_tina|backup-poc|Unable to initialize network service of TCP type, retex=TN_ERR_CONFLICT_RESS (conflict in access to the same resource)|0|~|~|~|~|~|~|
is it a potential that not enough share memory? since the tina_daemon use 2 ports which already define in the /etc/services
I feel very weird since when manually using root to restart the tina_daemon, everything works fine. When server restart with the startup script (which i changed to similar to manul restart), it does not work well for calling another executable to shutdown the application. It shutdown the application half way, and cause the application hang (and ultimate need to restart the application)