Thanks Julian, I understand /32 for "lo" interface. But my question is VIP for director, it usually configure in other interface than "lo" , what's the difference between /32 and actual subnet of the VIP.
In keepalived, if no netmask provide, vip will configure with /32 netmask, for example: virtual_ipaddress { 192.168.0.111 ; it will use /32 netmask 192.168.0.112/24 ; it will use /24 netmask } Thanks, Linbo 2017-06-22 5:10 GMT+08:00 Julian Anastasov <j...@ssi.bg>: > > Hello, > > On Sun, 18 Jun 2017, linbo liao wrote: > > > If vip 192.168.0.111 from subnet 192.168.0.0/24, and no netmask support > in > > configuration, the default netmask is 255.255.255.255. I test default > > netmask, looks everything works fine. > > > > So what's the proper netmask for vip, 255.255.255.255 or 255.255.255.0? > > The "lo" interface is special in Linux, if you > add IP/24 on lo, what is added actually is a range of local > addresses, i.e. 256 local addresses in the case for /24. > As result, for the 127.0.0.1/8 case, we actually have > 16,777,216 local addresses, i.e. you can use 127.0.0.1 but > also 127.0.0.2 ... 127.255.255.255. > > In the common case with IPVS, we add single VIP, so > only 255.255.255.255 should be used. And I don't think > 255.255.255.255 is a default mask, it should be specified in > all commands. > > Regards > > -- > Julian Anastasov <j...@ssi.bg> > _______________________________________________ Please read the documentation before posting - it's available at: http://www.linuxvirtualserver.org/ LinuxVirtualServer.org mailing list - lvs-users@LinuxVirtualServer.org Send requests to lvs-users-requ...@linuxvirtualserver.org or go to http://lists.graemef.net/mailman/listinfo/lvs-users