Sharing an IP address between two servers

Question

linux

There are two virtual servers with HAProxy hosted on different physical machines, the task is to make a failover, that is, raise the IP address on the machine that is currently available if the other stops responding.

All IP addresses are from the same pool, the broadcast is the same, but one machine does not see what the other sends to the broadcast, so solutions such as keepalived, ucarp, heartbeat are not suitable. Why they don’t see it, I don’t know, but since there is no access to either the network or the Xen hypervisors, nothing can be fixed from this side. What else can be used to achieve a result without a broadcast? (Sending to the broadcast is not a problem - you still have to send an ARP rikquest to the nearest router to change the IP. The problem is to read another VPSke from the broadcast).

Thank you.

Answer 1

I think that the bicycle was invented a long time ago. One of the options for this bike is called heartbeat - one line of the config writes what is written above for half a page

Answer 2

It's called VRRP
I advise you to use keepalived

Answer 3

the simplest failover can be done on scripts - an additional IP is allocated to the service, which is hung up as an alias on the interface due to inaccessibility, after which the service itself rises.