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# 1  
Old 09-19-2010
ipfw and dhcp

Hello,
I have a little problem with my server configuration.
So: I have two PC's with DHCP enable and both of them have two NIC's.

PC1 - le0 ADSL
PC1 - le1 192.168.10.1

PC2 - le0 192.168.10.10
PC2 - le1 192.168.20.1

One NIC on PC1 is connected to ADSL, another one have IP address 192.168.10.1
PC2 have 192.168.10.10 on the 1st NIC, and 192.168.20.1 on the 2nd.
When someone want to connect and his MAC is not configured in PC1 ( to take IP from 192.168.10.0 network ) he take IP address from DHCP from PC2 - 192.168.20.2.
The problem is that, when I type: /release /renew somethimes PC take IP address from ADSL - 192.168.1.17 How can I restrict/deny this range - 192.168.1.0?I don't wana my PC's to take IP's from there.
I try with: ipfw add 2 deny all from 192.168.1.0/24 to any;ipfw add 3 deny all from any to 192.168.1.0/24;ipfw add 4 deny all from any to 192.168.1.1 and many, many, but nothing works Smilie
And the second question is: when I ping from 192.168.10.1 to 192.168.10.10 ( another PC ), ping is < 1ms, but when I ping 192.168.20.1 ( another interface ), ping is too high ( like 2ms,8ms, 20ms and etc. ).It's not hardware problem in lan card, becouse interfaces are virtual.
# 2  
Old 09-19-2010
Are you running two DHCP servers? use static DHCP entries - eg: configure their MAC addresses to get the same IP each time. I have done this with ISC DHCP.

where is PC2:le1 plugged into physically?
# 3  
Old 09-19-2010
Yes I have two DHCP servers and also use fixed-address ( on the 1st one ).
On the 1st PC in dhcp.conf I have: range 192.168.10.3 192.168.10.3;
so when PC with no fixed-address connect, it's redirected to dhcp on PC2.

PC1 and PC2 are part of my VMWare Infrastructure.
PC2 le0 is definite like VM Nework Public, le1 is VM Network Private.

P.S. Something for packet filter for 192.168.1.0 ADSL network?How to restrict this network?

Last edited by mrowcp; 09-19-2010 at 07:35 PM..
# 4  
Old 09-26-2010
Ok, lets ask something else.

1) How to config my dhcp server ( or put some rule in ipfw ) to deny 192.168.10.3 to be distributed/used from PC's in my network?

2) When 1 laptop is connetced to my wireless network, its take IP 192.168.20.34 ( becouse laptop MACs is not configured in dhcp server to take ip from 192.168.10.0 network ).So I run: ipconfig /release and ipconfig /renew
Now laptop wana take IP 192.168.10.3, but I put this IP manualy like 2nd in my network adapter, so laptop can take it and in cmd I have this msg:

Quote:
C:\Documents and Settings\PC_User>ipconfig /renew

Windows IP Configuration

No operation can be performed on Local Area Connection while it has its media di
sconnected.
An error occurred while renewing interface Wireless Network Connection : The DHC
P client has obtained an IP address that is already in use on the network. The l
ocal interface will be disabled until the DHCP client can obtain a new address.
Wireless adapter continue to reconnecting and after 1.40min he take IP 192.168.20.34.
Why my dhcp server say: "IP address that is already in use on the network" This IP is released and no one use it.Is there any options in dhcp.conf for releasing time?

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