[Mageia-discuss] Temporarily changing IP address

Tue May 22 17:59:59 CEST 2012

> On 22/05/12 15:08, AL13N wrote:
+>>>>> No :-(  No difference, even though I restarted the network
+>>>>> service,
+>>>
+>>> Lets start from scratch.
+>>>
+>>> But first, can you tell me the ip address of the NAS and your
+>>> laptop's IP address for eth0.
+>>>
+>>> After making note of these, put the laptop back to it's original
+>>> config. (i.e. remove the manually created interface) and set
+>>> wlan0 not to come up on reboot.  Then restart so you only have an
+>>> ip address on eth0.
+>>>
+>>> Then send me the info.
+>>>
+>>> Doug
+>>
+>> in fact, if we want it to be even simpler, you could add the ip
+>> address without a alias interface wit iproute2
+>>
+>> []# ip addr show eth0
+>
+> # ip addr show eth0
+> 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast
+> state UP qlen 1000
+>     link/ether 1c:75:08:28:bd:e4 brd ff:ff:ff:ff:ff:ff
+>     inet 169.254.100.1/24 brd 169.254.100.255 scope global eth0
+>     inet6 fe80::1e75:8ff:fe28:bde4/64 scope link
+>        valid_lft forever preferred_lft forever
+>
+>> []# ip addr add www.xxx.yyy.zzz/netmask dev eth0
+>
+> # ip addr add www.192.168.0.20/255.255.255.0 dev eth0
+> Error: an inet prefix is expected rather than
+> "www.192.168.0.20/255.255.255.0".
+>
+> Not sure what it is expecting.
+
+hum, i meant the socalled CIDR notation: 4 parts of ip address followed by
+a subnet mask,
+
+in your case, i'd do:
+
+[]# ip addr add 192.168.0.20/24 dev eth0
+
+then if you do
+
+[]# ip addr show eth0
+
+again, you'd see it was there, as well as the extra route for that range:
+
+[]# ip route
+
+
+>>
+>> this will add an ip address on that interface, and
+>>
+>> []# ip route
+>>
+>> if you're done:
+>>
+>> []# ip addr del www.xxx.yyy.zzz/netmask dev eth0
+>>
+>> should now show you a route into that different subnet
+>>
+>> this means, no mess with alias interfaces or separate settings, or
+>> anything.
+>>
+>> to be sure, restart shorewall service (in the event it filters on
+>> the interface ip addresses)
+>
+> Shorewall and iptables are currently stopped.
+
+Be careful of this, in your case, it might not matter, but shorewall stop
+has policy DROP, (i think), allthough iptables should have policy ACCEPT.
+
+so, you'd have to stop shorewall first, then stop iptables.
+
+personally, i'd rather not stop the firewall, due to security reasons
+though. but since with this solution, you don't have any extra interface,
+even just restarting it would be fine.
+
+if you want to debug even further:
+
+[]# tcpdump -n -i eth0 host <nas_ip>
+
+and try to connect and then you can see what sourceip and destip are set
+and if a reply is coming back.
+
+