LAN Plugin kills Samba / freezes laptop (Edit: it doesn't)

Support for Android version of Total Commander

Moderators: Stefan2, white, sheep, Hacker

Post Reply
hgdorn
Junior Member
Junior Member
Posts: 18
Joined: 2009-04-22, 13:11 UTC
Location: Germany

LAN Plugin kills Samba / freezes laptop (Edit: it doesn't)

Post by *hgdorn » 2019-04-23, 08:09 UTC

I'm experiencing a strange behaviour of the LAN Plugin since a few months now, I don't know if I'm the only one with this problem, I even don't know if there's something wrong with TC's LAN Plugin, wih TC itself, with Samba or with Ubuntu or Debian.

Phenomenon: if I move lots of small files (e.g. pictures) from my S7 to a Samba share of my Ubuntu 16.04 laptop or my Debian 9 server, sooner or later the Ubuntu laptop freezes completely, Samba on my Debian server crashes and refuses further connections (smbd shows a locked file and cannot be restarted).

The Ubuntu laptop freezes during the first file is being moved, at least after some megabytes (2 to 4 or so), the Debian server's Samba stops working after some dozens of files. Unfortunately not reproducable, sometimes it runs without problems, the somtimes the phenomenon appears regularly.
  • TC (latest version *) with LAN Plugin (latest version *) on Samsung S7 with Android 8.0.0 (*) from Google Play Store
  • SMB2: it doesn't matter of I use SMB2 or not
  • LMv1: unchecked
  • old method...: unchecked
Either the Ubuntu laptop and the Debian server run smoothly and are used for backups where I regularly transfer gigabytes with rsync and smb, too, and normally they have an uptime of "months without any problems" as long as I don't "attack" them with the LAN plugin. Log files don't show anything. It doesn't matter if I access the laptop via WLAN or by LAN.

Any tips appreciated.


Edit: May be the same unsolved (?) issue as discussed here? https://www.ghisler.ch/board/viewtopic.php?f=22&t=50478
Last edited by hgdorn on 2019-04-25, 11:21 UTC, edited 2 times in total.
#9260

User avatar
ghisler(Author)
Site Admin
Site Admin
Posts: 37548
Joined: 2003-02-04, 09:46 UTC
Location: Switzerland
Contact:

Re: LAN Plugin kills Samba / freezes laptop

Post by *ghisler(Author) » 2019-04-23, 13:21 UTC

I haven't received any similar reports so far, so it's probably the server running unstable. No client should be able to make a server freeze, this would be a HUGE security hole.

TC uses two completely separate libraries for SMB1 and SMB2:
SMB1: jcifs
SMB2: smbj

It would be very strange if these two libraries would share the same bug causing this error. jcifs doesn't support SMB2 and smbj doesn't support SMB1, that's why I have to use these two. But it's strange that you have this with two different servers. Anyway, no server should crash due to a remote connection!
Author of Total Commander
http://www.ghisler.com

hgdorn
Junior Member
Junior Member
Posts: 18
Joined: 2009-04-22, 13:11 UTC
Location: Germany

Re: LAN Plugin kills Samba / freezes laptop

Post by *hgdorn » 2019-04-24, 08:28 UTC

Thanks for your answer, Christian.

Yes, indeed, it's very strange. I'll keep on investigating this issue.

Regarding the Debian server: I've crashed Samba with tranferring files from a Win7 client with TC 9.21a, too. So, I assume it's either a Linux/IP stack/Samba and/or a hardware problem. Not good, doesn't make fun to copy files and to reboot servers...

Edit: The systems do not crash or freeze but react very very very slow. Terminal input appears about five minutes later, but a "shutdown -r now" from there is possible.

I do not know what exactly is going on there but I do know that it has nothing to do with TC oder the LAN Plugin.
#9260

User avatar
ghisler(Author)
Site Admin
Site Admin
Posts: 37548
Joined: 2003-02-04, 09:46 UTC
Location: Switzerland
Contact:

Re: LAN Plugin kills Samba / freezes laptop

Post by *ghisler(Author) » 2019-04-25, 09:25 UTC

I see - maybe the system is running out of file handles or TCP/IP sockets due to the many small files transferred? It may be better to transfer one big ZIP file and then unpack it locally via SSH.
Author of Total Commander
http://www.ghisler.com

hgdorn
Junior Member
Junior Member
Posts: 18
Joined: 2009-04-22, 13:11 UTC
Location: Germany

Re: LAN Plugin kills Samba / freezes laptop

Post by *hgdorn » 2019-04-25, 11:14 UTC

My first guess was the existence of two network interfaces. It wasn't. Same Debian installation in a Virtual Box with as few RAM as the physical hardware runs without problems, thus I guess it's either a hardware problem or a specific hardware module problem. The Debian server shows the same symptoms when uploading files via FTP (from a Windows FTP client). And it hangs up even when I upload one big file via SMB or FTP. Why the laptop also crashes / hangs, who knows.

Total Commander and its LAN Plugin are definitely not the cause for my problems, they are working fine.
#9260

User avatar
ghisler(Author)
Site Admin
Site Admin
Posts: 37548
Joined: 2003-02-04, 09:46 UTC
Location: Switzerland
Contact:

Re: LAN Plugin kills Samba / freezes laptop (Edit: it doesn't)

Post by *ghisler(Author) » 2019-04-29, 13:44 UTC

The Debian server shows the same symptoms when uploading files via FTP
Does it only happen when uploading many small files? Then it's an indoication that the server is running out of file or connection handles.
Author of Total Commander
http://www.ghisler.com

hgdorn
Junior Member
Junior Member
Posts: 18
Joined: 2009-04-22, 13:11 UTC
Location: Germany

Re: LAN Plugin kills Samba / freezes laptop (Edit: it doesn't)

Post by *hgdorn » 2019-04-30, 07:52 UTC

ghisler(Author) wrote:
2019-04-29, 13:44 UTC
The Debian server shows the same symptoms when uploading files via FTP
Does it only happen when uploading many small files? Then it's an indoication that the server is running out of file or connection handles.
No, it crashes even with one big file (2 GB). It's an old and slow piece of hardware, I'm ignroring it now. My further investigations will concentrate on the laptop, if I will find some time...
#9260

hgdorn
Junior Member
Junior Member
Posts: 18
Joined: 2009-04-22, 13:11 UTC
Location: Germany

Re: LAN Plugin kills Samba / freezes laptop (Edit: it doesn't)

Post by *hgdorn » 2019-06-18, 20:46 UTC

Just for information: The following entries appeared in my syslog when starting to copy files via TC/LAN plugin to my Ubuntu laptop. Fortunately it didn't freeze and after two restarts of the kernel modules ("Hardware restart was requested") the files were copied successfully.

Code: Select all

Jun 18 22:37:16 tux wpa_supplicant[1227]: TDLS: Creating peer entry for 6c:c7:ec:0e:95:5b
Jun 18 22:37:16 tux kernel: [88569.915104] iwlwifi 0000:04:00.0: Microcode SW error detected.  Restarting 0x82000000.
Jun 18 22:37:16 tux kernel: [88569.915234] iwlwifi 0000:04:00.0: Start IWL Error Log Dump:
...
Jun 18 22:37:19 tux kernel: [88572.872493] ieee80211 phy0: Hardware restart was requested
I still don't know why this only happens when TC/LAN plugin is involved... (SMB2 was unchecked this time)
#9260

User avatar
ghisler(Author)
Site Admin
Site Admin
Posts: 37548
Joined: 2003-02-04, 09:46 UTC
Location: Switzerland
Contact:

Re: LAN Plugin kills Samba / freezes laptop (Edit: it doesn't)

Post by *ghisler(Author) » 2019-06-20, 09:43 UTC

I have googled "Microcode SW error detected. Restarting" and found this:
https://bugs.launchpad.net/ubuntu/+source/linux-firmware/+bug/1804841

It seems to happen with certain Intel wireless adapters. One user in this thread fixed it with this command:
echo "options cfg80211 cfg80211_disable_40mhz_24ghz=Y" > /etc/modprobe.d/cfg80211.conf
Author of Total Commander
http://www.ghisler.com

Post Reply