Script "nc-who" - similar to unix `who`, follow live who is logged in

[corsairius]

This is the most useful command out there, now.

I was a sysadmin, and it is critical to know who is on your system. I may have to dig out the code and write this to a file. I want to provide the other admins, who do not have access to the Ubuntu box, an update every few minutes.

This is good mojo.

I had this cheesed up for a hint as to who might be on. get-users-last-login-date

This is much handier!

Thanks!

[ernolf]

@corsairius

This is the most useful command out there, now.

Thank you for the appreciative feedback

@corsairius

I want to provide the other admins, who do not have access to the Ubuntu box,

For what Operating system do you need it? Maybe I can help to make it available for multiple OSes.

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ernolf

[corsairius]

This is utilized on Ubuntu 20.04 , but the monitor performs in a CLI, precluding use at the Nextcloud UI level. It would be helpful for a single-pass to show activity for active users. That output would be placed in a Note updated every few minutes so that the data is monitored at close enough intervals to show activity. Admins could then use that information to troubleshoot system issues, or just review system use.

Possibly beyond that, is similar to the System load monitor under the Administrative tab, exactly providing the currently provided activity status.

Even without that, there is finally a tool to indicate active users.

Thanks!
–Joe.

[corsairius]

Attempting to change some system parameters, and hours later restoring NC functionality, and received the following that I’m not yet able to resolve:

/tmp/nc-who78672_oqoYn5EpLzUY: line 17: q0: command not found
Error: You must install at least one postgresql-client- package

I’ve got matching versions to postgresql-16 and postgresql-client-16.

Not sure where to go here. Is this system configuration related or an init that is required, as those packages had to be reinstalled?

Thanks,
–Joe.

[ernolf]

Hi @corsairius,

@corsairius

Attempting to change some system parameters

The ebtb scripts and their modules cannot be changed that easily. They are the result of years of development. They are full of security layers that are designed to prevent the code from being changed. Tainted modules are immediately replaced with clean ones. After all, the scripts and modules are signed by me and as soon as you start tinkering with the script itself, things will at best no longer work. There’s a reason for everything. If you want to make changes, you should contact me via PM and explain exactly what you want to achieve.
I’ll then see if I can - and decide if I will help you.

Please don’t misunderstand me, but I cannot risk that scripts I have made publicly available could cause harm through changes.
The trust in my scripts that I have built up over the years is my most valuable asset. If that is destroyed, I can take everything offline.

h.t.h.

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Much and good luck,
ernolf

[corsairius]

I was not changing your utility’s system configuration. I was changing mine. There is no fault of your scripts here, and they are unchanged. I was curious as to my error in not seeing the postgresql-client call.

I was seeing if there was a remove and reinstall process, which may reread my system attributes on my Nextcloud instance.

thanks,
–Joe.

[ernolf]

What I can tell from this error:

@corsairius

/tmp/nc-who78672_oqoYn5EpLzUY: line 17: q0: command not found

EDIT:

Thank you for that feedback, I could reconstruct and fix it.

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@corsairius

Error: You must install at least one postgresql-client- package

“nc-who” speaks directly to the database and requires a command line client, either psql for postgreSQL or mysql for MariaDB. If no client is available or cannot be found, the operating system issues this error. At least it does not come from the script itself.
However, I would be interested to know if you can reconstruct the error without the script if you call psql.

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ernolf

[corsairius]

psql -p 5432 -h localhost -U nextcloud nextcloud
Password for user nextcloud: 
psql (16.6 (Ubuntu 16.6-1.pgdg20.04+1))
SSL connection (protocol: TLSv1.3, cipher: TLS_AES_256_GCM_SHA384, compression: off)
Type "help" for help.

nextcloud=> SELECT * FROM pg_user;
  usename  | usesysid | usecreatedb | usesuper | userepl | usebypassrls |  passwd  | valuntil | useconfig 
-----------+----------+-------------+----------+---------+--------------+----------+----------+-----------
 postgres  |       10 | t           | t        | t       | t            | ******** |          | 
 nextcloud |    16388 | f           | f        | f       | f            | ******** |          | 
(2 rows)

nextcloud=> 

But then it required a password to enter.

–Joe.

[ernolf]

@corsairius

But then it required a password to enter.

Of course you need the password when you connect “by feet” to the database comandline client. Because it does not have the magic of nc-who, nc-apps or nc-sql, handling the pasword stuf for you in the background.

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ernolf

[corsairius]

I haven’t seen anything new about this error in Brave searches, both AI and otherwise, except for the following issues with this particular error message.

Three items are indicated as resolution of the issue.

1. Install the postgresql-client-16 package.
2. Ensure the ‘psql’ binary is in the PATH variable.
3. Ensure the versions match between the Server and Client binaries.

So far uninstalling and reinstalling Postgresql-16, and harrowingly losing Nextcloud database a couple times, that hasn’t changed receipt of the error code. I’ve also uninstalled postgresql-common, and postgresql-client-common, kinda repeating the above heart attack stuff… But I know more about recovery and interactions with NC now.

I’m hoping that a re-init of nc-who would suffice?

Thanks!
–Joe.

[ernolf]

Hi @corsairius,

@corsairius

I haven’t seen anything new about this error

I have researched the problem you described to the bottom of it. At first I couldn’t explain it to myself because it worked perfectly for me in different environments, but in the end I was able to reconstruct it and implement a solution.

Please try again and give me feedback on whether it has now been solved for you.

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ernolf

[corsairius]

It works again. Thanks!

–Joe.

[corsairius]

Sent a coffee

[Aukfood85]

Hello, https://global-social.net seem not to work I couldn’t download nc-who.

Best regards

[Aukfood85]

@ernolf now it seems to work for download.

It is possible to see client IP in nc-who ?

[rakekniven]

Of which device of the user?

[ernolf]

@Aukfood85

It is possible to see client IP in nc-who ?

It is technically possible but I didn’t integrate that on purpose.

You can see the remote addresses from the → audit log ← file.

Here I described how to filter that:

Is there any admin_audit parameter to filter or limit events to be logged?

The audit.log is, as the nextcloud.log in json format. The great thing about json is its filterability. The command-line JSON processor jq is needed for this. Here some examples: Follow the audit.log in a compact format, beginning with the last 100 lines: tail -Fn 100 /path/to/audit.log | jq -r '[.time, .remoteAddr, .user, .method, .url, .message, .userAgent] | join(" - ")' tail -F /path/to/audit.log | jq -r 'select(.message | test("Login|Logout")) | [.time, .remoteAddr, .user, .method, .…

h.t.h.

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Much and good luck,
ernolf

[corsairius]

Is there a log file for what comes up in nc-who monitor? Space, I’ve got and can trim if there is a rotation capability.

Alas, jumping the gun pressing 2, after ‘nc-who monitor’ and received the error even upon reinstall:
checking modules - ansi/dev/fd/63: line 34: utf_filter: command not found

sudo wget -O /usr/local/bin/nc-who https://global-social.net/script/nc-who
--2025-03-14 21:06:10--  https://global-social.net/script/nc-who
Resolving global-social.net (global-social.net)... 84.152.103.82
Connecting to global-social.net (global-social.net)|84.152.103.82|:443... connected.
HTTP request sent, awaiting response... 302 Found
Location: https://global-social.net/apps/raw/scripts/nc-who [following]
--2025-03-14 21:06:11--  https://global-social.net/apps/raw/scripts/nc-who
Reusing existing connection to global-social.net:443.
HTTP request sent, awaiting response... 200 OK
Length: unspecified [text/plain]
Saving to: ??/usr/local/bin/nc-who??

/usr/local/bin/nc-who                [ <=>                                                       ]   9.78K  --.-KB/s    in 0.002s  

2025-03-14 21:06:11 (3.87 MB/s) - ??/usr/local/bin/nc-who?? saved [10017]

root@collins:~# sudo chmod +x /usr/local/bin/nc-who
root@collins:~# nc-who
.. checking modules - ansi/dev/fd/63: line 34: utf_filter: command not found
.. checking modules - dependency
  Dependency not met!

  missing dependency:
  ==============================================================================
  Binary          Package         Description
  ------------------------------------------------------------------------------
  ansifilter      ansifilter      parse common (terminal) ANSI codes and remove or convert them
  ------------------------------------------------------------------------------

Q: Do you want to install this package now? ([y]es or [n]o) [yes]: 
Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to locate package ansifilter
  looks like something went wrong.
exiting??

Thanks!
–Joe.

[bb77]

If you are on Ubuntu, maybe the Universe repo is not enabled for some reason. You can enable it with the following command:

sudo add-apt-repository universe

[ernolf]

Hi @corsairius

Thank you for your feedback!

@corsairius

checking modules - ansi/dev/fd/63: line 34: utf_filter: command not found

That was because of a wrong loading order of the filter module and has been fixed.

Regarding the dependency to ansifilter: I have removed it as a dependency and replaced it with a self written function as described here:

Php-updater - a script to upgrade php in a safe way

It’s a new dependency on the package ansifilter, which is normally available in the apt sources of Debian and Ubuntu: https://packages.debian.org/ansifilter https://packages.ubuntu.com/ansifilter Are you using a different distribution or a rare architecture? But to help you and others who might stumble upon this limitation, I removed the dependency on ansifilter and wrote a function that has the functionality of Ansifilter. ansifilter will still be used if it’s installed, but if it’s not i…

h.t.h.

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Much and good luck,
ernolf