Hi,
i did one more test on another machine (also debian 12) but with native
installed guacd.
No problem to connect concurrent to more than 70 hosts.
Than i fire up a guacamole in docker with the :latest official images on
the same host.
And i have the same effect on this host (16GB mem and 4core, instead of
6GB and 2Core) after 60 connections. I can't connect to any more hosts.
Instead of the problem described in
https://www.mail-archive.com/[email protected]/msg12565.html
after i close one active connection and the guacd-process for this is
gone, the not working connection is able to connect. This leads me to
the assumption that the problem is due to a limit of Docker or the
Alpine base image. Or I'm wrong?
Should i try to build the docker image against other alpine versions?
here are some infos about the native-install vs docker version running
Native Install/Host:
6.1.0-37-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.140-1 (2025-05-22)
x86_64 GNU/Linux
ii freerdp2-dev 2.10.0+dfsg1-1 amd64 Free Remote Desktop
Protocol library (development files)
ii libfreerdp-client2-2:amd64 2.10.0+dfsg1-1 amd64 Free
Remote Desktop Protocol library (client library)
ii libfreerdp-server2-2:amd64 2.10.0+dfsg1-1 amd64 Free
Remote Desktop Protocol library (server library)
ii libfreerdp-shadow-subsystem2-2:amd64 2.10.0+dfsg1-1 amd64
FreeRDP Remote Desktop Protocol shadow subsystem libraries
ii libfreerdp-shadow2-2:amd64 2.10.0+dfsg1-1 amd64
FreeRDP Remote Desktop Protocol shadow libraries
ii libfreerdp2-2:amd64 2.10.0+dfsg1-1 amd64 Free
Remote Desktop Protocol library (core library)
ii libssl-dev:amd64 3.0.16-1~deb12u1 amd64 Secure Sockets Layer
toolkit - development files
ii libssl-doc 3.0.16-1~deb12u1 all Secure Sockets Layer
toolkit - development documentation
ii libssl1.0.2:amd64 1.0.2u-1~deb9u7 amd64 Secure Sockets Layer
toolkit - shared libraries
ii libssl1.1:amd64 1.1.1w-0+deb11u2 amd64 Secure Sockets Layer
toolkit - shared libraries
ii libssl3:amd64 3.0.16-1~deb12u1 amd64 Secure Sockets Layer
toolkit - shared libraries
In the docker environment, with a startet rdp-session i see this via
"lsof -p 332043" (spawned guacd)
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
guacd 332043 cwd DIR 0,45 4096 1725749 /
guacd 332043 rtd DIR 0,45 4096 1725749 /
guacd 332043 txt REG 0,45 49384 1709877
/opt/guacamole/sbin/guacd
guacd 332043 mem REG 8,1 1709877
/opt/guacamole/sbin/guacd (stat: No such file or directory)
guacd 332043 mem REG 8,1 1709712
/opt/guacamole/lib/freerdp2/librdpgfx-client.so (stat: No such file or
directory)
guacd 332043 mem REG 8,1 1709672
/opt/guacamole/lib/freerdp2/libdisp-client.so (stat: No such file or
directory)
guacd 332043 mem REG 8,1 1709678
/opt/guacamole/lib/freerdp2/libguac-common-svc-client.so (stat: No such
file or directory)
guacd 332043 mem REG 8,1 1709809
/opt/guacamole/lib/libssh2.so.1.0.1 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1709738
/opt/guacamole/lib/*libfreerdp2.so.2.11.7* (stat: No such file or directory)
guacd 332043 mem REG 8,1 1709733
/opt/guacamole/lib/*libfreerdp-client2.so.2.11.7* (stat: No such file or
directory)
guacd 332043 mem REG 8,1 1709848
/opt/guacamole/lib/libwinpr2.so.2.11.7 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1709755
/opt/guacamole/lib/libguac-client-rdp.so.0.0.0 (stat: No such file or
directory)
guacd 332043 mem REG 8,1 1717165
/usr/lib/libmd.so.0.0.5 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1716768
/usr/lib/libbsd.so.0.11.7 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1716762
/usr/lib/libbrotlicommon.so.1.0.9 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1716732
/usr/lib/libXdmcp.so.6.0.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1716730
/usr/lib/libXau.so.6.0.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1716764
/usr/lib/libbrotlidec.so.1.0.9 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1716770
/usr/lib/libbz2.so.1.0.8 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1716785
/usr/lib/libexpat.so.1.10.1 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1717366
/usr/lib/libsharpyuv.so.0.0.1 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1717321
/usr/lib/libpixman-1.so.0.42.2 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1717716
/usr/lib/libxcb-shm.so.0.0.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1717693
/usr/lib/libxcb-render.so.0.0.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1717768
/usr/lib/libxcb.so.1.1.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1716738
/usr/lib/libXrender.so.1.3.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1716734
/usr/lib/libXext.so.6.4.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1716728
/usr/lib/libX11.so.6.4.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1716793
/usr/lib/libfreetype.so.6.19.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1716789
/usr/lib/libfontconfig.so.1.12.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1705933
/lib/libz.so.1.2.13 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1717599
/usr/lib/libwebp.so.7.1.8 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1715161
/lib/libuuid.so.1.3.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1715043
/lib/libcrypto.so.1.1 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1717336
/usr/lib/libpng16.so.16.44.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1717125
/usr/lib/libjpeg.so.8.2.2 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1716774
/usr/lib/libcairo.so.2.11708.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1715145
/lib/*libssl.so.1.1* (stat: No such file or directory)
guacd 332043 mem REG 8,1 1709805
/opt/guacamole/lib/libguac.so.25.0.0 (stat: No such file or directory)
guacd 332043 mem REG 8,1 1705918
/lib/ld-musl-x86_64.so.1 (stat: No such file or directory)
guacd 332043 0u CHR 1,3 0t0 5 /dev/null
guacd 332043 1w FIFO 0,13 0t0 7995649 pipe
guacd 332043 2w FIFO 0,13 0t0 7995650 pipe
guacd 332043 3u sock 0,8 0t0 7996605 protocol: UNIX
guacd 332043 4u sock 0,8 0t0 7996606 protocol: TCP
guacd 332043 5u sock 0,8 0t0 8085998 protocol: TCP
guacd 332043 6u a_inode 0,14 0 1048 [eventfd:22]
guacd 332043 7u sock 0,8 0t0 8087212 protocol: UNIX
guacd 332043 8u sock 0,8 0t0 8087215 protocol: UNIX-STREAM
guacd 332043 9u a_inode 0,14 0 1048 [eventfd:23]
guacd 332043 10u a_inode 0,14 0 1048 [eventfd:24]
guacd 332043 11u a_inode 0,14 0 1048 [eventfd:25]
guacd 332043 12u a_inode 0,14 0 1048 [eventfd:26]
guacd 332043 13u a_inode 0,14 0 1048 [eventfd:27]
guacd 332043 14u a_inode 0,14 0 1048 [eventfd:28]
guacd 332043 15u a_inode 0,14 0 1048 [eventfd:29]
guacd 332043 16u a_inode 0,14 0 1048 [eventfd:30]
guacd 332043 17u a_inode 0,14 0 1048 [eventfd:31]
guacd 332043 18u a_inode 0,14 0 1048 [eventfd:32]
guacd 332043 19u a_inode 0,14 0 1048 [eventfd:33]
guacd 332043 20u a_inode 0,14 0 1048 [eventfd:34]
guacd 332043 21u a_inode 0,14 0 1048 [eventfd:35]
guacd 332043 22u a_inode 0,14 0 1048 [eventfd:36]
guacd 332043 23u a_inode 0,14 0 1048 [eventfd:37]
guacd 332043 24u a_inode 0,14 0 1048 [eventfd:38]
guacd 332043 25u a_inode 0,14 0 1048 [eventfd:39]
guacd 332043 26u a_inode 0,14 0 1048 [eventfd:40]
guacd 332043 27u a_inode 0,14 0 1048 [eventfd:41]
guacd 332043 28u a_inode 0,14 0 1048 [eventfd:44]
guacd 332043 29u a_inode 0,14 0 1048 [eventfd:45]
guacd 332043 30u a_inode 0,14 0 1048 [eventfd:46]
guacd 332043 31u sock 0,8 0t0 8087836 protocol: TCP
guacd 332043 32u a_inode 0,14 0 1048 [eventfd:47]
guacd 332043 33u a_inode 0,14 0 1048 [eventfd:48]
guacd 332043 34u a_inode 0,14 0 1048 [eventfd:49]
On the native Install
guacd 332434 guacd mem REG 8,1 688160 2108404
/usr/lib/x86_64-linux-gnu/libssl.so.3
...
guacd 332434 guacd mem REG 8,1 732352 2097194
/usr/lib/x86_64-linux-gnu/libfreerdp-client2.so.2.10.0
guacd 332434 guacd mem REG 8,1 1530200 2097190
/usr/lib/x86_64-linux-gnu/libfreerdp2.so.2.10.0
...
guacd 332434 guacd mem REG 8,1 83504 2097933
/usr/lib/x86_64-linux-gnu/freerdp2/libguac-common-svc-client.so
in general many more libs loaded.
Maybe this helps to get to the right direction with this problem.
Tobias
Am 28.07.2025 um 18:48 schrieb Tobias Feller | OPC:
Hi Sean,
i all ready send Nick some infos...
I think it is not a general problem with the system resources. because
on different servers we always hit the 60+ limit. Maybe a combination
of docker, debian 12 as host and some generic limits (i don't know) in
default system config.
Here was my test with 60+1 opened rdp-sessions (chrome browser
windows) on a smaller test-machine (docker, gucad 1.6) that is running
on a Debian 12 host - no remote usage at all. but as you see the
spawned guacd-processes are there 1 per each active session + 1 for
the guacd-demon.
After 60+1 i can't connect any more...
guacd | guacd[67639]: DEBUG: guac_rdp_fs_close: Closed "\" (file_id=0)
*guacd | guacd[67639]: DEBUG: SSL_CTX_new failed
guacd | guacd[67639]: DEBUG:
transport_connect_tls:freerdp_set_last_error_ex
ERRCONNECT_CONNECT_CANCELLED [0x0002000B]*
guacd | guacd[67639]: DEBUG: SVC "rdpdr" disconnected.
and also seen this..
guacd | guacd[67838]: DEBUG: guac_rdp_fs_close: Closed "\" (file_id=0)
*guacd | guacd[67838]: DEBUG: BIO_should_retry returned a system
error 32: Broken pipe
guacd | guacd[67838]: DEBUG:
transport_write:freerdp_set_last_error_ex
ERRCONNECT_CONNECT_TRANSPORT_FAILED [0x0002000D]
guacd | guacd[67838]: DEBUG: BIO_should_retry returned a system
error 32: Broken pipe
guacd | guacd[67838]: DEBUG:
transport_write:freerdp_set_last_error_ex
ERRCONNECT_CONNECT_TRANSPORT_FAILED [0x0002000D]*
guacd | guacd[67838]: DEBUG: freerdp_post_connect failed
Hi
best regards,
Tobias
Am 28.07.2025 um 18:27 schrieb Sean Hulbert:
On 7/28/2025 3:22 AM, Tobias Feller | OPC wrote:
Hi Nick, Hi Alex,
@Nick
/"I've got a very similar environnent (guacd 1.5.5 on CentOS 7), and
it's been running for several weeks with hundreds of connections
having been made with it and I've not seen this issue."/
The Problem was for me only on *concurrent connections*. I'm running
also the 1.5.5 (docker) on our two guacamole (Loadbalanced) Hosts
since some month without problems. but with this 2 hosts we don't
hit the 60 concurrent connection limit at the moment.
Maybe i can try to do a test on another standby host that is using
1.6 and connect via some servers to 60 hosts at the same time.
Tobias
Am 28.07.2025 um 12:07 schrieb Alex_Yin:
I am running guacd 1.5.5 on Centos 7.9 vm
---- Replied Message ----
From Nick Couchman<[email protected]> <mailto:[email protected]>
Date 07/28/2025 17:54
To user<[email protected]> <mailto:[email protected]>
Subject Re: [EXT] SSH Connection Limit of 60 per guacd
On Mon, Jul 28, 2025 at 04:21 Alex_Yin <[email protected]> wrote:
Hello Julian,
Thank you for your suggestion. My problem is indeed very
similar to the link you provided. I also found this bug link
https://issues.apache.org/jira/browse/GUACAMOLE-1998. It seems
that it has not been solved yet. I found two solutions from
these two links:
1. Use version 1.5.3;
2. Build guacd image based on Debian 12.
I think I can try to roll back to version 1.5.3 first.
What version of guacd are you running when you encounter this?
Part of the challenge with the issue linked above is that we've
been unable to reproduce the issue reliably - I've got a very
similar environnent (guacd 1.5.5 on CentOS 7), and it's been
running for several weeks with hundreds of connections having been
made with it and I've not seen this issue. There must be some other
factor contributing to producing this behavior, we just haven't
figured that out, yet.
-Nick
