[HCoop-Discuss] Frank's confusion

[Adam Chlipala]

Clinton Ebadi wrote:
> Adam Chlipala <adamc at hcoop.net> writes:
>   
>> This seems like a deliberately disingenuous argument.  If we weren't 
>> using a network filesystem, then a failure of network hardware wouldn't 
>> break the filesystem.  It's that simple.
>>     
>
> Yes, it would break everything instead.
>
> Instead we are merely lacking the read only copy of our afs volumes and
> a secondary KDC which is causing the underlying issues with deleuze to
> be more noticeable (transient failure to check credentials -> failure
> instead of checking krunk and succeeding).
>   

We must be talking past each other here.  krunk is filling a role that 
doesn't exist in a system without distribution.  Naturally, if the 
network card fails on the machine where the files live, then services 
based on those files aren't going to get out into the world.  The 
problem in our case is that, compared to a monolithic server with a 
local filesystem, we have strictly increased the number of network cards 
whose failures can break things.  Under any reasonable assumptions about 
independence of card failures, this increases that chance that some 
network card will fail in a way that interferes with file access.