I bought a new ip address for my dedicated server on Ubuntu 16.04, and I've been trying to set it up, but I just consistently run into one issue; I'm unable to restart the networking service proper, even with the original config. This is what I get through systemctl status networking.service;
systemd[1]: Starting Raise network interfaces...
ifup[24985]: RTNETLINK answers: File exists
ifup[24985]: Failed to bring up eth0.
postconf: warning: /etc/postfix/master.cf: undefined parameter: mua_client_restrictions
networking.service: Main process exited, code=exited, status=1/FAILURE
Failed to start Raise network interfaces.
networking.service: Unit entered failed state.
networking.service: Failed with result 'exit-code'.
Here are the contents of the interfaces file (I've censored the addresses of course);
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet static
address xxx.xx.xx.146
netmask 255.255.255.0
network xxx.xx.xx.0
broadcast xxx.xx.xx.255
gateway xxx.xx.xx.254
auto eth0:0
iface eth0:0 inet static
address yy.yy.yyy.153
netmask 255.255.255.255
post-up /sbin/ifconfig eth0:0 yy.yy.yyy.153 netmask 255.255.255.255 broadcast yy.yy.yyy.153
pre-down /sbin/ifconfig eth0:0 down
I get this error with both the original file (copied over from the .bak file) and the edited file with the new IP. The networking service simply fails to run for an unspecified reason. If I try to ifup eth0 directly, I get the "File exists" and "Failed to bring up eth0" lines. Yet, despite shutting down, the IPs seem to get set properly in the interface configuration; they are properly mapped to the corresponding interfaces (eth0, eth0:0) and the corresponding Apache/Postfix/Dovecot installations also seem to be functional.
Yet when looking through networkctl, this is the result I get;
WARNING: systemd-networkd is not running, output will be incomplete.
IDX LINK TYPE OPERATIONAL SETUP
1 lo loopback n/a unmanaged
2 bond0 ether n/a unmanaged
3 dummy0 ether n/a unmanaged
4 ifb0 ether n/a unmanaged
5 ifb1 ether n/a unmanaged
6 eth0 ether n/a unmanaged
7 eth1 ether n/a unmanaged
8 teql0 void n/a unmanaged
9 tunl0 tunnel n/a unmanaged
10 sit0 sit n/a unmanaged
11 ip6tnl0 tunnel6 n/a unmanaged
The interface name is clearly eth0 and not something else. I'm wondering if some kind of dhcp service is interfering or if another service actually manages the interfaces. I don't think that NetworkManager is installed as the only way to get the server to be pingable again after flushing eth0 is to attempt to start networking, but networking still crashes on the same error. What I'm afraid of is that this will cause the server to be unpingable on a hard restart.
Does anyone have advice concerning the issue?
EDIT1: Here's ifconfig -a, here it is for eth0 and eth0:0
eth0 Link encap:Ethernet HWaddr 0c:c4:7a:c3:4e:f2
inet addr:xxx.xx.xx.146 Bcast:xxx.xx.xx.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2283 errors:0 dropped:0 overruns:0 frame:0
TX packets:251 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:149408 (149.4 KB) TX bytes:41071 (41.0 KB)
eth0:0 Link encap:Ethernet HWaddr 0c:c4:7a:c3:4e:f2
inet addr:yy.yy.yyy.153 Bcast:yy.yy.yyy.153 Mask:255.255.255.255
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
eth1 Link encap:Ethernet HWaddr 0c:c4:7a:c3:4e:f3
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)
Here's what happens in var/log/syslog, could it be an issue with postfix?
Jun 16 09:26:32 www postfix[3583]: * Reloading Postfix configuration...
Jun 16 09:26:32 www postfix[3588]: Postfix is running with backwards-compatible default settings
Jun 16 09:26:32 www postfix[3588]: See http://www.postfix.org/COMPATIBILITY_README.html for details
Jun 16 09:26:32 www postfix[3588]: To disable backwards compatibility use "postconf compatibility_level=2" and "postfix reload"
Jun 16 09:26:32 www postfix/master[1773]: reload -- version 3.1.0, configuration /etc/postfix
Jun 16 09:26:32 www postfix[3583]: ...done.
Jun 16 09:26:32 www systemd[1]: Reloaded LSB: Postfix Mail Transport Agent.
Jun 16 09:26:32 www systemd[1]: networking.service: Main process exited, code=exited, status=1/FAILURE
Jun 16 09:26:32 www systemd[1]: Failed to start Raise network interfaces.
Jun 16 09:26:32 www systemd[1]: networking.service: Unit entered failed state.
Jun 16 09:26:32 www systemd[1]: networking.service: Failed with result 'exit-code'.
