[Samba] Samba Replication

[Steve Francia]

We don't need 100mbit access, but the current implementation is too  
slow. Despite having fairly large pipes. Windows Clients have a ton of  
latency especially when working with remote files in Office. Due to  
the way windows/office are written the entire system freezes when a  
write or read operation is taking place.

Because of our workflow it is unlikely that collisions will happen (a  
person in office A editing the same file at the same time as a person  
in office B), so Unison may work. I wonder what the overhead would be  
cronning it that often. Unison seems to be a good fit here though.

The remote offices both have high download speeds, but cap out at T1  
upload speeds. So saving files is the big issue here. Files can be  
easily up to 15Mb routinely, though most will be around 1Mb. It is  
hard to find a microsoft office file under 100k now a days.

DFS in samba seems like a good approach, but doesn't it depend on a  
clustered file system for replication? Am I missing something here?


On Apr 18, 2008, at 1:37 PM, Adam Williams wrote:
> what do you mean by local speed access?  you mean they need 100mbit/ 
> gigabit speed to their files?  are they streaming DVD rips?  if both  
> offices just need the same file share, look at DFS in samba.  rsync  
> is one way mirroring, have you looked at Unison (two way file  
> syncing) and croning it to run every minute?  http://www.cis.upenn.edu/~bcpierce/unison/
>
> what sort of speed are the remote offices to each other?  t1's or  
> dsl/cable?  you could just have one office also shared to the samba  
> share on office two.  but if its anything more then files over 100K  
> in size they'll notice a little latency.
>
> Steve Francia wrote:
>> Hello, I have the following situation:
>>
>> I have two offices, which both require local speed access to their  
>> file
>> shares. Currently there is a single windows server that provides  
>> network
>> shares to both offices, the remote one through a vpn.
>>
>> I have used Samba since the early days, and am quite familiar with  
>> it's
>> capabilities and limitations, however I have never tried to perform
>> replication with it.
>>
>> My current plan, which certainly has some limitations is to take 2  
>> samba
>> servers, put one in each office. Rsync the two every half an hour.  
>> This will
>> provide redundancy and solve the major problem at hand, but will  
>> introduce
>> new problems.
>>
>> 30 minutes is too long, and users may work on the same file  
>> simultaneously
>> resulting in a conflict and changes lost.
>>
>> Has anyone approached this problem before?
>> What replication options work well with the current stable build of  
>> samba?
>> Is there any way to replicate when a file is locked, so the user  
>> will get
>> the warning that the file is locked?
>>
>> Any feedback would be helpful, even if it is a link.
>>
>> Thanks in advance,
>> Steve Francia
>>
>