[bird graceful restart time] Is there any way to set graceful restart time?

[이재용]

Hello,

We use BIRD for communication with servers with higher-level switches.
In our config , there is config to set graceful restart like below.

protocol bgp example2 {
        import all;
        export all;

        ...

        graceful restart on;
}

As far as I know, the default value for graceful restart is 120 seconds.
But I don't know how to change this time.
Please give me some advice on this. Thank you.