May i knw , is there any way to stop detecting external drives , can be usb's or hd , any command or so ..
Thanks in advance

You don't want to detect external drives? Easy, don't plug them in.
There doesn't seem much point having external drives plugged in if you cannot access them... perhaps you use them to weight your computer down for use in high winds? Or, possibly the question needs to be rephrased.

if i'm managing a LAN , if i'm the admin , how can protect the client to undetect pendrives , for security reasons i need to perform that operation ..

If there truly are "security reasons" then the first aspect to address is an information security policy describing what will be handled, how it must be handled and who is authorised to handle it. You'll want infrastructure security, procedures and work instructions, actually compartmentalising the information, access controls and auditing in terms of infrastructure, storage, workstations, software and let's not forget the minute details like making sure it's all legal and employees actually signing their (changed) contracts. *Then* you can worry about disabling peripherals in the BIOS, tweaking the kernel, tweaking HAL and Udev (see PolicyKit) and all other aspects like searching people for paper copies, photos on phones and portable media, LAN isolation, traffic monitoring, et cetera.

Without policy you have no allow/deny rules. Without rules to enforce you are not able to track and "teach" (heh) offenders. Without repercussions Chaos reigns. If there truly are "security reasons" then don't make the mistake thinking solely disabling USB in the BIOS does the trick. It takes a wee bit more than that. (See ISO/IEC 27002).

Sorry - I don't see how it is useful for your clients to have their pendrives "undetected" - unless you mean that, right now, every pendrive plugged in to any computer on your network is available as a shared resource to any user?

You handle that situation with the authorization level of your network access system. Jut don't give users access to other user's drives.

I think you need to rethink what you mean by "security" and "protect".

(I'm glad you got the joke - I have been flamed for that sort of thing before...)

Basically - if the device is not detected, it cannot be accessed.
Do you want to stop clients using usb devices on networked machines?
(Suspect - this is why unSpawn is talking about disabling USB in BIOS. You can also remove the driver, block the path, or just bung up the usb port. You'll find anyone serious has a very direct attitude to security.)

You could try

Hi Catkin - welcome to LQ.
Interesting suggestion - won't that make the external device unavailable to the owner?

Thanks Simon

Yes it will make the external device unavailable to the user.

I think that's OK -- vibinlakshman has not specified that he wants the device(s) to be available to the user, only that he doesn't want them to be detected.

Best

Charles

Yes I noticed - it can be fun to answer the question as stated, however, it is common for people not to know how to phrase their problem as a question - particularly if English is not their first language.

This leads to the much more challenging task of working out what OP actually wants to achieve.

It seems odd, does it not: surely if OP wanted to disable UMS devices, this would be asked? Really we need to know what it is that is happening now which is not wanted. Perhaps he just doesn't want UMS devices to appear (as an icon) on the desktop?

Whatever - some respondent will have supplied the answer needed, or we'll get a redirect. I'm curious to see what OPs reply will be.

May i please knw whether u r answering for my query or used to demonstrate ur English , do u think the above thread correspons to good English , i mentioned thread in order to understand even to people who doesnt speak or write English properly , thats why used to post thread little bit mixture of colloquialism .. U knw only only ur mother tongue , but we indian can speak ,write , read more than 3 languages , which u cudnt afford my friend
Try to humble which will make u perfect ..

I'm sorry, I'm not sure I understand what you are trying to say ... or who you are talking to. Let me tell you how I read that and you can correct me...

I suspect that you think that someone is criticizing your English. Let me assure you that this is not the case. For my part, I was attempting to advise caution to another that the question written down is not always what the questioner wants to know.

However - it looks like you could be saying that you think someones replies are too complicated in language ("used to demonstrate your English") for you to understand. If this is the case, then please point out the part that was giving you trouble so it can be made clear.

If you have received a reply which answers your query, please say so. If not, please refine your query so that those responding can refine their answers. This is why I asked the questions that I did. That is how we arrive at good answers which work for you.


BTW: Lets see if I can still do this...
Ce qui vous incite à me penser seulement sachez l'anglais,
es gibt viele Sprachen -
e molta gente può parlare più di una lingua:
tenga por favor más cuidado

... hmmm... seems I can mess up in five languages.

Hello Simon

It's a balance between clarifying what the questioner wants to know and giving a quick response. In this case thread the OP question seems clear, despite the unusual English. It asks how to stop removable media from being detected.

The question does not seem odd. Maybe OP has untrusted workers with access to confidential data and wants to prvent them copying GiBs of it to removable media. Maybe medical records, financial figures, membership records ...

I didn't know what UMS devices were until now (thanks -- a useful term).

Best

Charles

OK the guy who knows 5 languages .. Let me give a scenario

If in a institute where lab exams are to be conducted , where students are advised not to google for answers , obviously they wont listen , so sys admin had blocked online facility . So other choice wud be for students is to use an external disk like usb's ..
How can sys admin think wisely ? He would be supposed to close the ports of usb's been detecting , right ?
How can he do it ?

This was my simple question , that created this much fuss

Hello Lakshman :-)

I think hal-disable-polling can do it but I don't know what the device names have to be. Time to experiment, plugging in a selection of devices? When I insert a USB memory stick on ubuntu 8.04.2, it's /dev/sdb1. CD/DVDs come up as /dev/scd0.

BTW, where are you in Kerala? I'm in Tamil Nadu, in Auroville near Puducherry.

Best

Charles

got it. Do you need the ports permanently disabled or just for exams?

The hal method could be worked in to a script so admins can turn it on or off ... but it may be trouble to impliment system-wide, I don't know how you are set up.

Th access-controls approach will work system wide - just switch off student access to external media. I don't know what access control mechanisms the sysadmins use, so cannot really advise more specifically.

I'm sorry you think that getting a reply right for you is "such a fuss". I'm afraid it cannot be helped.