[ 
https://issues.apache.org/jira/browse/NET-685?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Simone updated NET-685:
-----------------------
    Description: 
Hello Everybody,

we implemented a multithread scheduler in order to run many FTP connections 
(one for each customer). We use these connections to upload /download files 
from/to remote servers.

Inside the scheduler, we use a ScheduledThreadPoolExecutor to run our FTP 
connections (about 50). We run one thread (which instantiates an FTPClient 
object) for each FTP connection.

Sometimes, one of those connections tries to connect to the FTP server and the 
method FTPClient.connect() hangs without any timeout. No log. No server 
response.
 The connection is blocked as well as the whole JVM. 

We needed to restart the service to fix the production.

We already checked the following points during the issue:
 - the server is reachable;
 - No overlapping between run threads;
 - the virtual machine runs correctly;
 - Every other connection works correctly (FTPS, SFTP, CIFS, ...) so far.

(Production logs attached)

PULL-REQUEST link: [https://github.com/apache/commons-net/pull/51]

Thanks in advance,
 Simone

  was:
Hello Everybody,

we implemented a multithread scheduler in order to run many FTP connections 
(one for each customer). We use these connections to upload /download files 
from/to remote servers.

Inside the scheduler, we use a ScheduledThreadPoolExecutor to run our FTP 
connections (about 50). We run one thread (which instantiates an FTPClient 
object) for each FTP connection.

Sometimes, one of those connections tries to connect to the FTP server and the 
method FTPClient.connect() hangs without any timeout. No log. No server 
response.
The connection is blocked as well as the whole JVM. 

We needed to restart the service to fix the production.

We already checked the following points during the issue:
- the server is reachable;
- No overlapping between run threads;
- the virtual machine runs correctly;
- Every other connection works correctly (FTPS, SFTP, CIFS, ...) so far.

(Production logs attached)


Thanks in advance,
Simone


> FTPClient.connect() hangs without any timeout and response. It blocks the 
> whole JVM
> -----------------------------------------------------------------------------------
>
>                 Key: NET-685
>                 URL: https://issues.apache.org/jira/browse/NET-685
>             Project: Commons Net
>          Issue Type: Bug
>          Components: FTP
>    Affects Versions: 3.6
>         Environment: *OS:* Debian 9
> *Java Version:* 1.8
> *Scheduler:* On made development using Spring-boot. Multithreading 
> Environment using Runnable Class.
>  
>            Reporter: Simone
>            Priority: Blocker
>         Attachments: ProductionLogsApache.txt
>
>
> Hello Everybody,
> we implemented a multithread scheduler in order to run many FTP connections 
> (one for each customer). We use these connections to upload /download files 
> from/to remote servers.
> Inside the scheduler, we use a ScheduledThreadPoolExecutor to run our FTP 
> connections (about 50). We run one thread (which instantiates an FTPClient 
> object) for each FTP connection.
> Sometimes, one of those connections tries to connect to the FTP server and 
> the method FTPClient.connect() hangs without any timeout. No log. No server 
> response.
>  The connection is blocked as well as the whole JVM. 
> We needed to restart the service to fix the production.
> We already checked the following points during the issue:
>  - the server is reachable;
>  - No overlapping between run threads;
>  - the virtual machine runs correctly;
>  - Every other connection works correctly (FTPS, SFTP, CIFS, ...) so far.
> (Production logs attached)
> PULL-REQUEST link: [https://github.com/apache/commons-net/pull/51]
> Thanks in advance,
>  Simone



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

Reply via email to