[OpenAFS-devel] diagnosing my problem with ubik elections... bug in ubik

[Hartmut Reuter]

"Neulinger, Nathan" wrote:
> 
> I did find one bug in ubik code... this isn't the complete solution to my
> problem, but I figured I'd send this to fix if I'm not confused. This bug
> explains the weird symptoms I was seeing with the hosts not getting the
> correct lowestHost.
> 
> in vote.c around line 208:
> 
>     if (!amIClone &&
>         (ntohl((afs_uint32) ubik_host) <= ntohl((afs_uint32) lowestHost)
>         || lowestTime + BIGTIME < now)) {
>         lowestTime = now;
>         lowestHost = ubik_host[0];
>     }
> 
> the comparison is wrong... should be:
> 
>     (ntohl((afs_uint32) ubik_host[0]) <= ntohl((afs_uint32) lowestHost)

This is my fault! We were, however, running with this code without
problems for years. I am sorry for this inconvenience.

Hartmut



> 
> As it is, you're comparing the ntohl of a pointer to lowestHost, so it's
> always updating lowest_host to be ubik_host[0]. (itself)
> 
> Once I changed that, the lowestHost calculation is looking much better.
> Still not syncing up cause no one is ever sending a yes vote, but I'm still
> looking at that.
> 
> -- Nathan
> 
> ------------------------------------------------------------
> Nathan Neulinger                       EMail:  nneul@umr.edu
> University of Missouri - Rolla         Phone: (573) 341-4841
> Computing Services                       Fax: (573) 341-4216
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> OpenAFS-devel mailing list
> OpenAFS-devel@openafs.org
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-- 
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Hartmut Reuter                           e-mail reuter@rzg.mpg.de
					   phone +49-89-3299-1328
RZG (Rechenzentrum Garching)               fax   +49-89-3299-1301 
Computing Center of the Max-Planck-Gesellschaft (MPG) and the
Institut fuer Plasmaphysik (IPP)
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