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Re: deny access
From: GuidoZ <uberguidoz () gmail com>
Date: Mon, 6 Dec 2004 14:20:09 -0500

This was well written....

And, technically speaking,

"access-list 101 deny ip source ip destination ip"

is the correct syntax, but the information he didn't get was:

There is an implicit "deny any any" in all Cisco ACLs, which means a 1
line ACL to block one host would effectively block all hosts.
&
ACL built, but it still needs bound

From interface config mode,

"ip access-group 101 in interface "

is the second part of the equation.
&
If there are no ACLs now, make it a two liner, the deny line, and:
access-list 101 permit ip any any

Again, well said. This was the point I was trying to make by saying
"Don't just give the answer because it could lead to trouble later".
Carlos needs to LEARN more about his device BEFORE trying to secure it
and make changes. Otherwise he'll just be more lost and possibly
create more problems.

I would be the first one to lend a hand (and have done so off-list),
however you (as in everyone) needs to use judgement when dealing with
such things. Factor in all values before coming to a soution. Again, I
have explained how and why I said and did what I did.

--
Peace. ~G


On Tue, 30 Nov 2004 19:51:46 -0500, Paris E. Stone <pstone () alhurra com> wrote:
~Begin Chastise~
He posted to the SECURITY-BASICS mailing list.
That would pretty much "determine the correct level of help" in my mind.
~End Chastise~
~
~Begin pathetic attempt at help~

And, technically speaking,

"access-list 101 deny ip source ip destination ip"

is the correct syntax, but the information he didn't get was:

There is an implicit "deny any any" in all Cisco ACLs, which means a 1
line ACL to block one host would effectively block all hosts.
&
ACL built, but it still needs bound

From interface config mode,

"ip access-group 101 in interface "

is the second part of the equation.
&
If there are no ACLs now, make it a two liner, the deny line, and:
access-list 101 permit ip any any

~End pathetic attempt at help~

My .02



-----Original Message-----
From: richardw [mailto:richardw () area52 allserve net]
Sent: Monday, November 29, 2004 11:11 PM
To: GuidoZ
Cc: Carlos Garcia; Agarwal, Ankur; security-basics () securityfocus com
Subject: Re: deny access

Everyone, I want to take this opportunity to apologize for Guido.
Carlos, if you still need help, email me off the list, and we'll help
get squared away.

Saludos,

Richard

GuidoZ wrote:
This is why I said it was better for him to find the answers on his
own, and not just tell him the ACL format. Otherwise it's very likely
that something will get messed up and he won't be able to fix it, or
ask questions online. ;)

Think about things before you act everyone. There is certainly nothing
wrong with helping out someone in need, although, you must determine
the correct level of help.

--
Peace. ~G


On Thu, 25 Nov 2004 19:40:40 -0700, Carlos Garcia
<carlosg () cabonet net mx> wrote:

ok i just write
access-list 101 deny ip host 216.212.33.185 any is this ok?
i put too
access-list 101 deny ip 216.212.33.185 255.255.255.255 any...
and can somebody tell me how to improve this, i run some servers and i
want
to protec them
mail, web,dns,proxy's where can i find a list so that it helps me how
to
configure the router to support QoS i need it for VoIP service???
thanks for
all the help

Atte.
Carlos A. Garcia G.
Cabonet Staff
Tel (624) 14 30120


----- Original Message -----
From: "Agarwal, Ankur" <Ankur.Agarwal () colt-telecom com>
To: "'Carlos Garcia'" <carlosg () cabonet net mx>;
<security-basics () securityfocus com>
Sent: Thursday, November 25, 2004 7:17 PM
Subject: RE: deny access


HI
Simply create an deny access list to block this IP.

Access-list 101 deny ip source ip destination ip



Thanks & Regards,

___________________________________________________
Ankur Agarwal



One Dial : 8-911-7428
Tel : +91 124 5157000 (Ext. 2272)
*Cell : +91 9810702016



COLT India
ankur.agarwal () colt-telecom com

___________________________________________________




-----Original Message-----
From: Carlos Garcia [mailto:carlosg () cabonet net mx]
Sent: 25 November 2004 04:58
To: security-basics () securityfocus com
Subject: deny access


newbie question how can i block this ip 216.212.33.185 i have a cisco
7200
this ip is trying to send mail with my server, i did not configure
the
router so i dont know how to do this any help?


Atte.
Carlos A. Garcia G.
Cabonet Staff
Tel (624) 14 30120



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--
------------------------------------------------------------------------
   ____/\___  |                                     | "If you can't beat
   ___/__\__) |              richardw               | them, then they're
  (__/    \__ | mailto:richardw!area52.allserve.net | not tied down good
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