req.restart or director to provide high availability

Poul-Henning Kamp phk at
Fri Sep 12 20:37:33 CEST 2008

In message <48CAAE62.8060508 at>, jean-marc pouchoulon writes:
>I "implement" req.restart to provide high availbility, changing the 
>backend if req.restart > 0
>But I saw that director skips backend if it is unaivalable.
>Both of them provides the same fonctionnality regards to high 
>availability or Did I misunderstand something ?

well, they _can_ overlap.

restarts are more flexible, for instance, instead of changing
the backend you could change the url or some other header when
the first attempt didn't work.

The directors only disable backends based on when their probe
requests fail, not on when a "production" request fails.

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

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