Issue After Plesk upgrade FTP storage in Backup manager - curl error (56)

[Arcthurus]

Hi there,

since we have upgraded from Plesk 12.5 to Onyx 17.0.17 the FTP storage in Backup Manager is broken.

We use Onyx on current Centos 7.3 and connecting to a pure-ftpd Server (1.43 on Ubuntu 16.04 LTS) via FTPs. Before the upgrade it worked flawless.

Now plesk shows following error message:

Transport error: unable to list directory: Curl error: (56) Failure when receiving data from the peer: Last FTP request: LIST -a Last FTP response: 150 Accepted data connection

FTPs still works fine to pure-ftpd via FileZilla. Just curl is somehow broken on Onyx Backup Manager

 

[IgorG]

Make sure that ftp server is accessible from you Plesk server and you can login with ftp credentials.
Then try to upload backup file manually from your Plesk server with command like:

# curl -v -k --ftp-ssl ftp://xxx.xxx.xxx.xxx//backups/ --user <ftpuser>:<ftp_pass> --upload-file backup.zip

and check errors in the output.

 

[Arcthurus]

Hi,

thank you for the reply. After facing a problem with the password and special chars (@ and $) given directly in the password of the command line -> permission denied.

I then tested the behavior to leave the password free in the curl command so that it is asking me later. After entering the password I could then upload the files still with the original password using special chars, but curl error 56. For debugging purpose I removed the special chars in my password. Still the same curl error (56) failed directory listing. Here is the output of curl (I have changed all the personal data)

# curl -v -k --ftp-ssl ftp://example.org//archives/ --user myuser:mysecretpw --upload-file test
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
0 0 0 0 0 0 0 0 --:--:-- --:--:-- --:--:-- 0* About to connect() to example.org port 21 (#0)
* Trying 1.1.1.1...
* Connected to example.org (1.1.1.1) port 21 (#0)
< 220---------- Welcome to Pure-FTPd [privsep] [TLS] ----------
< 220-You are user number 2 of 50 allowed.
< 220-Local time is now 12:27. Server port: 21.
< 220-This is a private system - No anonymous login
< 220-IPv6 connections are also welcome on this server.
< 220 You will be disconnected after 15 minutes of inactivity.
> AUTH SSL
< 500 This security scheme is not implemented
> AUTH TLS
< 234 AUTH TLS OK.
* Initializing NSS with certpath: sql:/etc/pki/nssdb
* skipping SSL peer certificate verification
* SSL connection using TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
* Server certificate:
* REMOVED
> USER myuser
< 331 User myuser OK. Password required
> PASS mysecretpw
< 230-OK. Current restricted directory is /
< 230 0 Kbytes used (0%) - authorized: 307200000 Kb
> PBSZ 0
< 200 PBSZ=0
> PROT P
< 200 Data protection level set to "private"
> PWD
< 257 "/" is your current location
* Entry path is '/'
> CWD /archives
* ftp_perform ends with SECONDARY: 0
< 250 OK. Current directory is /archives
> EPSV
* Connect data stream passively
< 229 Extended Passive mode OK (|||51340|)
* Trying 1.1.1.1...
* Connecting to 1.1.1.1 (1.1.1.1) port 51340
* Connected to example.org (1.1.1.1) port 21 (#0)
> TYPE I
< 200 TYPE is now 8-bit binary
> STOR test
< 150 Accepted data connection
* Doing the SSL/TLS handshake on the data stream
* skipping SSL peer certificate verification
* SSL connection using TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
* Server certificate:
* REMOVED
} [data not shown]
* We are completely uploaded and fine
* Remembering we are in dir "/archives/"
* response reading failed
100 5 0 0 100 5 0 26 --:--:-- --:--:-- --:--:-- 26
* Connection #0 to host example.org left intact
curl: (56) response reading failed

 

[Bitpalast]

I guess this has something to do with the SSL certificate configuration used on the host or on the FTP destination. After upgrading to Onyx, have you created and/or updated the host SSL certificate?

 

[Arcthurus]

Hi,

thank you for your hint, but how could this have anything to do with the SSL certificate? On both hosts I use a Lets encrypt certificate which works in both ways (tested with filezilla windows client, and curl on the plesk server shows the right certificate from the ftp host - I removed the data from the log therefore I left "REMOVED")

With filezilla I don't have any problems with directory listing of the ftp storage host (pure-ftpd), after upgrading plesk 12.5 to 17.0.17 I now have a problem with curl on the directory listing, uploading files works with curl at least on command line.

PS: didn't change the SSL certificates.

 

[Arcthurus]

Ok, I have now found a not totally satisfying workaround which makes me use the ftp-storage again. On the FTP-Storage Host I turned on "Broken Clients Compatibility" in Pure-FTPd. -> The Directory listing via Curl works again and Plesk Backup Managers is connecting to the FTP Storage.

I just wonder what has triggered the need of turning on the "Broken Clients Compatibility", any ideas?

PS: I've also tested Plesk Onyx on a second machine with Centos 6, and receiving the same behavior with "curl error (56)"