directory-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Emmanuel L├ęcharny <>
Subject Questions regarding Aliases
Date Tue, 24 Apr 2012 11:28:30 GMT
Hi guys,

Aliases handling is one of the biggest challenge in LDAP, as it imposes 
a lot of constraints. First of all, keep in mind that Alias support is 
not mandatory.

Some of the problem we have when dealing with Alaises are :
- cycle detection : we should not allow the creation of an alias that 
causes a cycle
- duplicated entry removals in searches : we shuld not return an entry 
that has already been returned
- unlinked aliases : when the aliased entry is removed, we should should 
handle it
- subtree searches with aliases : we may have a very high nunber of 
entries to return
- move operation : how do we handle the aliases modification when the 
aliased entries is move ?
- cross-partitions aliases : how do we handle them ?
- replication of aliases

Right now, my concern is about duplicated entries removal and cycle 
detection, during a search processing :

1) Cycle detection :
Should we assume that the cycles are detected during the alias creation 
? Or should we detect it while processing the search ? (I'm nclined to 
think that cycle are forbidden during their creation)

2) duplicated entries removal
I don't see any other way but storing a hash of all the UUID we already 
have transmitted, and to check when we have a new candidate if this 
candidate has already been processed. This is potentially *extremely* 
costly, if we have millions of entries (even if there is a size limit, 
which protects us from a OOM, because this size limit is not enforced 
for the manager user).
Is there a better way ?

3) Current Aliases index
I didn't have time to check what those index are used for, so if someone 
can give me a quick heads up, that would save me a few days of code 

Many thanks !

Emmanuel L├ęcharny

View raw message