Just a cautionary note, if you use snmpd you may start seeing regular "ia_addr insert" errors using this approach depending on your version of snmpd and how reporting is configured.
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________________________________________ From: CentOS centos-bounces@centos.org on behalf of Ulf Volmer u.volmer@u-v.de Sent: Friday, February 8, 2019 11:48 AM To: centos@centos.org Subject: [EXTERNAL] Re: [CentOS] netmask on aliases overriden by netmask on interface
On 08.02.19 15:08, James B. Byrne via CentOS wrote:
# ifconfig eth1:192008001 eth1:192008001 Link encap:Ethernet HWaddr 00:25:90:61:74:C1 inet addr:192.168.8.1 Bcast:192.168.8.255 Mask:255.255.255.128 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:17 Memory:feae0000-feb00000
Which shows that the network mask is determined by the interface mask and is not overridden by the alias definition.
Is this expected behaviour? Does this mean that a particular physical interface cannot belong to more than one network, or at least not to networks having differing cidr masks?
Interface aliases are evil from my point of view. I recommend to configure the ip directly to the interface.
#ifcfg-eth2 [...] IPADDR=192.168.200.1 NETMASK=255.255.255.0 IPADDR2=192.168.201.1 NETMASK2=255.255.255.192
ip addr show dev eth2 4: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 08:00:27:b0:c5:7c brd ff:ff:ff:ff:ff:ff inet 192.168.200.1/24 brd 192.168.200.255 scope global eth2 inet 192.168.201.1/26 brd 192.168.201.63 scope global eth2 inet6 fe80::a00:27ff:feb0:c57c/64 scope link valid_lft forever preferred_lft forever
Best regards Ulf _______________________________________________ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos