Tons sshguard log entries and its not enabled
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id either extend the lease times or give them static ips, But I am a novice. Still learning myself
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@johnpoz I upped the log size and I’ll monitor for now. I did isolate another logging issue that is specific to ESP WiFi/networking chips used in IOT devices. I have 2 WiFi weather stations in the house that are connected to my IOT VLAN. These devices that use the ESP chips and are so dumb that they don’t handle DHCP in the traditional manner. Regardless of when the DHCP server tells the client to renew their IP address, these clients renew their IP address EVERY MINUTE…and I have 2 of them. These devices are so crappy they get dropped by my Unifi access points after 1-2 hours. I use an old Asus router as an access point just to connect these devices. I’m sure this was the cause of much DHCP log rotation.
My solution was to make the Asus router a router again and shift weather station IP management to the Asus getting the noise off of Pfsense. Pfsense assigns the IP address to the Asus and I keep all of these devices in the IOT VLAN. Of course the best solution would be to toss these weather stations in the trash but this will work for now.
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Hi,
PfSense CE 2.6.0
As a workaround I tried disabled the log packets matched from the default block rules in the ruleset to reduce the amount of system logs, but after a period of calm, the problem has returned.
I changed the log file size from 500K to 1024 and didn't work either. After about a day the logs became polluted again.
In my case, the filter logs are very large and i need them.
I haven't found a solution for this yet. This "dirt" in the logs can hinder the visibility of some critical event.Jul 8 12:17:00 sshguard 27403 Exiting on signal.
Jul 8 12:17:00 sshguard 86043 Now monitoring attacks.
Jul 8 12:19:00 sshguard 86043 Exiting on signal.
Jul 8 12:19:00 sshguard 71802 Now monitoring attacks.
Jul 8 12:21:00 sshguard 71802 Exiting on signal.
Jul 8 12:21:00 sshguard 52201 Now monitoring attacks.
Jul 8 12:23:00 sshguard 52201 Exiting on signal.
Jul 8 12:23:00 sshguard 32915 Now monitoring attacks.
Jul 8 12:25:00 sshguard 32915 Exiting on signal.
Jul 8 12:25:00 sshguard 76907 Now monitoring attacks.
Jul 8 12:27:00 sshguard 76907 Exiting on signal.
Jul 8 12:27:00 sshguard 52340 Now monitoring attacks.Geovane
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@geovaneg your saying you have a log file rotating every 2 minutes? Yeah I could see how that would be problematic.
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Hi @johnpoz
Yes:
[2.6.0-RELEASE][admin@pfsense]/var/log: ls -tal | grep filter
-rw------- 1 root wheel 585448 Jul 8 12:48 filter.log
-rw------- 1 root wheel 110227 Jul 8 12:47 filter.log.0.bz2
-rw------- 1 root wheel 77990 Jul 8 12:44 filter.log.1.bz2
-rw------- 1 root wheel 101983 Jul 8 12:42 filter.log.2.bz2
-rw------- 1 root wheel 78511 Jul 8 12:39 filter.log.3.bz2
-rw------- 1 root wheel 88127 Jul 8 12:37 filter.log.4.bz2
-rw------- 1 root wheel 109005 Jul 8 12:35 filter.log.5.bz2
-rw------- 1 root wheel 82652 Jul 8 12:32 filter.log.6.bz2 -
@geovaneg your going to need to limit how much your logging, or go with a much larger size log file.. maybe 10M vs 1, or even like 100M? That seems like a lot of logging ;)
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thank you to reply @johnpoz
I found it strange that for some time after I change the settings (about a day) the problem stopped but returns later. Also, in previous versions the amount of logs was the same and the problem did not occur.
Do you have any idea why this change in behavior?
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The logs switched from the circular log format back to the default BSD format. That means they have to be rotated and sshguard restarts whenever any log is rotated.
https://docs.netgate.com/pfsense/en/latest/releases/2-5-0.html?highlight=clog#loggingSteve
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@stephenw10 said in Tons sshguard log entries and its not enabled:
sshguard
Thank you @stephenw10
I understood.
But the previous version of this server was already 2.5.1 and it didn't have the excess of sshguard logs, with the same volume of logs and I imagine with the same rotation frequency of them.
This is what struck me as strange.
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@geovaneg can you not limit the stuff your logging in some way? And also up the log file size?
So at a 2 min rotation for 1M and only keeping what 6 rotations - the amount of logs is only the last 12 minutes anyway - how is that even useful?
edit: my math off, with current log and 6 rotated (0-6 = 7) at most you would have like 16 minutes ;)
edit2: none of what is being logged is noise that you could just not log? I would think you would want atleast 24 hours of logs? Mine go back like 3 days and only storing 5 rotations. Are you also sending to say syslog as well?
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Yeah you should be using an external syslog server there.
In 2.5.1 the same applies so it can really only have been that the logs were not rotating. Eother the logs were far larger or there was far less to log.
Steve
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Hi Guys.
Yes, logs are sent to a remote syslog server.
This PfSense server serves a large wireless network and I need to retain the fw logs for possible future audits.
I still have 4 other VPN servers that I haven't updated to version 2.6.0. They are in 2.5.2. I must face the same problem with them as they produce a lot of logs.I ran a test just now:
I manually reset the syslog, via graphical console: Status->Services->Syslogd<Restart Service>Jul 8 15:21:59 pfsense syslogd: exiting on signal 15
Jul 8 15:21:59 pfsense syslogd: kernel boot file is /boot/kernel/kernelWe can see that the files keep rotating:
[2.6.0-RELEASE][admin@pfsense]/var/log: ls -tal | grep filter
-rw------- 1 root wheel 940974 Jul 8 15:35 filter.log
-rw------- 1 root wheel 116009 Jul 8 15:34 filter.log.0.bz2
-rw------- 1 root wheel 127082 Jul 8 15:32 filter.log.1.bz2
-rw------- 1 root wheel 114071 Jul 8 15:30 filter.log.2.bz2
-rw------- 1 root wheel 92094 Jul 8 15:28 filter.log.3.bz2
-rw------- 1 root wheel 101016 Jul 8 15:26 filter.log.4.bz2
-rw------- 1 root wheel 93269 Jul 8 15:24 filter.log.5.bz2
-rw------- 1 root wheel 103993 Jul 8 15:22 filter.log.6.bz2However, there are no more "sshguard" messages in the system logs until I forced an event into the log (logout and login to the web interface), which seems to have "waked up" the problem again.:
Jul 8 15:18:00 sshguard 25670 Exiting on signal.
Jul 8 15:18:00 sshguard 10773 Now monitoring attacks.
Jul 8 15:20:00 sshguard 10773 Exiting on signal.
Jul 8 15:20:00 sshguard 95347 Now monitoring attacks.
Jul 8 15:21:59 syslogd exiting on signal 15
Jul 8 15:21:59 syslogd kernel boot file is /boot/kernel/kernel
Jul 8 15:27:45 nginx 2022/07/08 15:27:45 [error] 2540#100160: send() failed (54: Connection reset by peer)
Jul 8 15:40:28 php-fpm 89546 /index.php: User logged out for user 'admin' from: remote-machine (Local Database)
Jul 8 15:40:31 php-fpm 89546 /index.php: Successful login for user 'admin' from: remote-machine (Local Database)
Jul 8 15:40:31 sshguard 13794 Now monitoring attacks.
Jul 8 15:42:00 sshguard 13794 Exiting on signal.
Jul 8 15:42:00 sshguard 93750 Now monitoring attacks.
Jul 8 15:44:00 sshguard 93750 Exiting on signal.Could you help me understand why manual reset interrupts sshguard log records for a while, even though there is rotation?
Thanks
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Hmm, that looks more a bug in sshguard that stops it running....
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Yeah, the processes should look like:
root 77695 0.0 0.1 11384 2824 - Ss 13:03 0:00.24 |-- /usr/sbin/syslogd -s -c -c -l /var/dhcpd/var/run/log -P /var/run/syslog.p root 63461 0.0 0.1 11524 3048 - Is 20:41 0:00.00 | `-- /bin/sh /usr/local/sbin/sshguard -i /var/run/sshguard.pid root 63916 0.0 0.1 10620 2224 - I 20:41 0:00.00 | |-- /bin/cat root 63956 0.0 0.2 17420 4420 - IC 20:41 0:00.00 | |-- /usr/local/libexec/sshg-parser root 64030 0.0 0.1 12072 2796 - IC 20:41 0:00.00 | |-- /usr/local/libexec/sshg-blocker root 64102 0.0 0.2 11524 3052 - I 20:41 0:00.00 | `-- /bin/sh /usr/local/sbin/sshguard -i /var/run/sshguard.pid root 64566 0.0 0.1 11492 3044 - I 20:41 0:00.00 | `-- /bin/sh /usr/local/libexec/sshg-fw-pfBut after restarting syslogd manually:
root 38082 0.0 0.1 11372 2820 - Ss 20:44 0:00.00 |-- /usr/sbin/syslogd -s -c -c -l /var/dhcpd/var/run/log -P /var/run/syslog.pid -f /etc/syslog.confAnd logging out and back in restarts it:
Jul 8 20:49:47 sshd 77257 Received disconnect from 172.21.16.5 port 58362:11: disconnected by user Jul 8 20:49:47 sshd 77257 Disconnected from user admin 172.21.16.5 port 58362 Jul 8 20:49:47 sshguard 26522 Now monitoring attacks. Jul 8 20:49:52 sshd 27315 Accepted keyboard-interactive/pam for admin from 172.21.16.5 port 58364 ssh2Hmm
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Ok, it's not really a bug because the process is restarted as soon as there is a login attempt. And it still locks you out after three bad attempts.
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@stephenw10 you could even call it a feature ;)
Why run a process if there is nothing to do.. Until there is a login attempt why monitor a log for something that isn't happening ;)
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Mmm, but that begs the question, why run it continually at all?
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Following this line of reasoning, I wonder: is it really necessary for sshguard to keep recording in the system log each time it restarts along with rotate, if it is really protecting the ssh service?
Is there another unwanted side effect of the rotate occurring every 2 minutes? It wouldn't matter much to me, as long as it doesn't fill up my filesystem, as the logs are sent remotely.
Isn't there a way to disable sshguard restart log in the system logs? -
@stephenw10 said in Tons sshguard log entries and its not enabled:
Mmm, but that begs the question, why run it continually at all?
exactly!
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In some systems the CPU required to compress the logs when rotates can become significant. It's worth disabling the compression if that's the case.
