On Tue, Aug 9, 2016 at 8:16 PM, Tom Browder <tom.brow...@gmail.com> wrote:
> I have read the current Debian networking docs on the subject
> (https://wiki.debian.org/NetworkConfiguration#iproute2_method). I
> want to use at least two IPv4 static addresses on the same physical
> NIC. Following examples I have tried this in my
> "/etc/network/interfaces" file:
...
I have now had success on my test host running Debian on my local
network. Below is a working "/etc/network/interfaces" file, but there
are some warnings, notes, and caveats for its use. Note also the file
is IDENTICAL to the one I asked about originally. I went down a
rabbit hole because the "service networking restart" command locked me
out of my test host and I couldn't get back in locally because I had
an KVM failure I didn't know about. Just today I got all working
again.
1. WARNING: The following command, mentioned in the some networking
docs (like the one mentioned by my server hosting company!!!), caused
a system lock-up and loss of all network contact external to or
internal from the host:
# service networking restart.
However, a subsequent reboot worked. That might be impossible or
expensive to do if you do not have direct access (i.e., non-network)
access to the host.
2. CAUTION: I have not tried all the various if* or ip commands on the
test host. Your mileage may vary.
The "/etc/network/interfaces" file:
=======================
# The loopback network interface
auto lo
iface lo inet loopback
# The primary network interface
allow-hotplug eth0
iface eth0 inet static
address 192.168.0.17
netmask 255.255.255.0
gateway 192.168.0.1
dns-nameservers 208.67.222.222 208.67.220.220
up ip addr add 192.168.0.18/24 dev $IFACE label $IFACE:0
down ip addr del 192.168.0.18/24 dev $IFACE label $IFACE:0
up ip addr add 192.168.0.19/24 dev $IFACE label $IFACE:1
down ip addr del 192.168.0.19/24 dev $IFACE label $IFACE:1
RESULTS
=======
Running "sbin/ifconfig" on the test host (with two NICs: one used and
one unused, and the two new alias IPv4s) yields:
eth0 Link encap:Ethernet HWaddr 00:1d:7d:aa:fa:7b
inet addr:192.168.0.17 Bcast:192.168.0.255 Mask:255.255.255.0
inet6 addr: fe80::21d:7dff:feaa:fa7b/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:735 errors:0 dropped:0 overruns:0 frame:0
TX packets:749 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:82025 (80.1 KiB) TX bytes:101457 (99.0 KiB)
eth0:0 Link encap:Ethernet HWaddr 00:1d:7d:aa:fa:7b
inet addr:192.168.0.18 Bcast:0.0.0.0 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
eth0:1 Link encap:Ethernet HWaddr 00:1d:7d:aa:fa:7b
inet addr:192.168.0.19 Bcast:0.0.0.0 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
eth1 Link encap:Ethernet HWaddr 00:15:e9:81:14:b4
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:123 errors:0 dropped:0 overruns:0 frame:0
TX packets:123 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:49276 (48.1 KiB) TX bytes:49276 (48.1 KiB)
I can ssh into the test host using all three IPv4s.
NOTES
=====
RECOMMENDATIONS
================
Test network changes on a host that you have direct access to!!!!
Thanks for the help Pascal, and I hope this will help someone else.
Best regards,
-Tom
