Blocking IP range

hohohann · 01-14-2008, 06:35 AM

Hi there,

The firewall in my office is running on Linux Redhat.
Every workstations' IP address is being assigned by the firewall using DHCP. I want to block/reserve a range of 20 IP addresses from 10.10.10.10 to 10.10.10.30 for future use.
In future, i want to allocate static IP from the mentioned range to certain new workstation.
How do i go about it?

Thanks.

odcheck · 01-14-2008, 07:03 AM

no sweat
just edit your /etc/dhcpd.conf
there you can specify this range not to be served.

Jirka11 · 01-14-2008, 07:05 AM

Quote:

Originally Posted by hohohann

Hi there,

The firewall in my office is running on Linux Redhat.
Every workstations' IP address is being assigned by the firewall using DHCP. I want to block/reserve a range of 20 IP addresses from 10.10.10.10 to 10.10.10.30 for future use.
In future, i want to allocate static IP from the mentioned range to certain new workstation.
How do i go about it?

Thanks.

In your /etc/dhcpd.conf you should use
range 10.10.10.1 10.10.10.9
range 10.10.10.31 10.10.10.254

or directly reserv some IP addresses by:

host some-printer {
hardware ethernet 08:00:2b:4c:59:23;
fixed-address 10.10.10.10;
}
....
....

_____________________________________________
http://www.nmonitoring.com

hohohann · 01-14-2008, 09:27 AM

Quote:

Originally Posted by odcheck

no sweat
just edit your /etc/dhcpd.conf
there you can specify this range not to be served.

What are the commands like to specify the range not to be served?
thanks in advance.

Emerson · 01-14-2008, 09:33 AM

First - see man pages
Second - Google
Still stuck? Ask your questions here.

http://linux.die.net/man/5/dhcpd.conf

hohohann · 01-14-2008, 07:59 PM

Quote:

Originally Posted by Jirka11

host some-printer {
hardware ethernet 08:00:2b:4c:59:23;
fixed-address 10.10.10.10;
}

How do i determine the hostname of that particular hardware (printer, computer....) ?

odcheck · 01-15-2008, 03:31 AM

@hohohann

no problem just post me your /etc/dhcpd.conf
but please use (["code"] and paste [/code"])

or the otherway around

Code:

next-server             192.168.1.100;
option root-path        "192.168.1.100:/opt/ltsp/i386";

subnet 192.168.1.0 netmask 255.255.255.0 {            <---Here just shrink the iprange
    range   192.168.1.100   192.168.1.199;
    if substring (option vendor-class-identifier, 0, 9) = "PXEClient" {
        filename "/lts/2.6.16.1-ltsp-2/pxelinux.0";
    }
    else{
        filename "/lts/vmlinuz-2.6.16.1-ltsp-2";
    }
}
#
# If you need to pass parameters on the kernel command line, you can
# do it with option-129.  In order for Etherboot to look at option-129,
# you MUST have option-128 set to a specific value.  The value is a
# special Etherboot signature of 'e4:45:74:68:00:00'.
#
# Add these two lines to the host entry that needs kernel parameters
#
#        option option-128     e4:45:74:68:00:00;       # NOT a mac address
#        option option-129     "NIC=ne IO=0x300";

hohohann · 01-16-2008, 01:47 AM

@odcheck

Let say i want to reserve a range of IP (10.10.10.150 t0 10.10.10.180) not to be distributed by DHCP. Can i do as follow:

Code:

# Sample /etc/dhcpd.conf
# (add your comments here)
ddns-update-style interim;
ignore client-updates;
subnet 10.10.10.0 netmask 255.255.255.0 { 
range 10.10.10.10 10.10.10.149; 
range 10.10.10.181 10.10.10.254;
default-lease-time 86400; 
max-lease-time 86400; 
option subnet-mask 255.255.255.0; 
option broadcast-address 10.10.10.255; 
option routers 10.10.10.1; 
option domain-name-servers 10.10.10.1, 202.75.129.101, 202.75.129.102, 210.19.58.2; 
option netbios-name-servers 10.3.4.3; 
option domain-name "abc.com"; option ip-forwarding off; 
option netbios-node-type 2;

	host SIEB_DB_MON {
		hardware ethernet 00:10:b5:cc:b1:1f;
		fixed-address 10.10.10.2;
	}
}

akthktd · 01-16-2008, 08:17 AM

How can I unblock sites in my college ?

We are using RedHat.

I want to log on to orkut.com

thanks

odcheck · 01-17-2008, 12:43 AM

@hohohann that should do the Trick :-)

and @akthktd how nice :-) then do it
this has nothing to do with this Thread, please open a new one.