Re: [MooseFS-Users] MooseFS 4.0 and new features

[Alexander A. <ba...@ya...>]

Hi All!

Is it true? I'm asking about "MooseFS Pro also includes a Windows client."

If yes where can I read more about it?



On 20.05.2018 16:08, Marin Bernard wrote:
>>> This is very interesting
>>> Any official and detailed docs about the HA feature?
>>>
>>> Other than this, without making any flame, which are the
>>> differences
>>> between MFS4 and LizardFS?
>>>
>> Hi again,
>>
>> I've been testing both MooseFS 3.0.x and LizardFS 3.1x in parallel
>> for
>> a few weeks now. Here are the main differences I found while using
>> them. I think most of them will still be relevant with MooseFS 4.0.
>>
>> * High availability
>> In theory, LizardFS provides master high-availability with
>> _shadow_  instances. The reality is less glorious, as the piece of
>> software actually implementing master autopromotion (based on uraft)
>> is
>> still proprietary. It is expected to be GPL'd, yet nobody knows when.
>> So as of now, if you need HA with LizardFS, you have to write your
>> own
>> set of scripts and use a 3rd party cluster manager such as corosync.
>>
>> * POSIX ACLs
>> Using POSIX ACLs with LizardFS requires a recent Linux Kernel (4.9+),
>> because a version of FUSE with ACL support is needed. This means ACLs
>> are unusable with most LTS distros, whose kernels are too old.
>>
>> With MooseFS, ACLs do work even with older kernels; maybe because
>> they
>> are implemented at the master level and the client does not even try
>> to
>> enforce them?
>>
>> * FreeBSD support
>> According to the LizardFS team, all components do compile on FreeBSD.
>> They do not provide a package repository, though, nor did they
>> succeed
>> in submitting LizardFS to the FreeBSD ports tree (bug #225489 is
>> still
>> open on phabricator).
>>
>> * Storage classes
>> Erasure coding is supported in LizardFS, and I had no special issue
>> with it. So far, it works as expected.
>>
>> The equivalent of MooseFS storage classes in LizardFS are _custom
>> goals_. While MooseFS storage classes may be dealt with
>> interactively,
>> LizardFS goals are statically defined in a dedicated config file.
>> MooseFS storage classes allow the use of different label expressions
>> at
>> each step of a chunk lifecycle (different labels for new, kept and
>> archived chunks). LizardFS has no equivalent.
>>
>> One application of MooseFS storage classes is to transparently delay
>> the geo-replication of a chunk for a given amount of time, to lower
>> the
>> latency of client I/O operations. As far as I know, it is not
>> possible
>> to do the same with LizardFS.
>>
>> * NFS support
>> LizardFS supports NFSv4 ACL. It may also be used with the NFS Ganesha
>> server to export directories directly through user-space NFS. I did
>> not
>> test this feature myself. According to several people, the feature,
>> which is rather young, does work but performs poorly. Ganesha on top
>> of
>> LizardFS is a multi-tier setup with a lot of moving parts. I think it
>> will take some time for it to reach production quality, if ever.
>>
>> In theory, Ganesha is compatible with kerberized NFS, which would be
>> far more secure a solution than the current mfsmount client, enabling
>> its use in public/hostile environments. I don't know if MooseFS 4.0
>> has
>> improved on this matter.
>>
>> * Tape server
>> LizardFS includes a tape server daemon for tape archiving. That's
>> another way to implement some kind of chunk lifecycle without storage
>> classes.
>>
>> * IO limits
>> Lizardfs includes a new config file dedicated to IO limits. It allows
>> to assign IO limits to cgroups. The LFS client negotiates its
>> bandwidth
>> limit with the master is leased a reserved bandwidth for a given
>> amount
>> of time. The big limitation of this feature is that the reserved
>> bandwidth may not be shared with another client while the original
>> one
>> is not using it. In that case, the reserved bandwidth is simply lost.
>>
>> * Windows client
>> The paid version of LizardFS includes a native Windows client. I
>> think
>> it is built upon some kind of fsal à la Dokan. The client allows to
>> map
>> a LizardFS export to a drive letter. The client supports Windows ACL
>> (probably stored as NFSv4 ACL).
>>
>> * Removed features
>> LizardFS removed chunkserver maintenance mode and authentication code
>> (AUTH_CODE). Several tabs from the Web UI are also gone, including
>> the
>> one showing quotas. The original CLI tools were replaced by their own
>> versions, which I find harder to use (no more tables, and very
>> verbose
>> output).
>>
>>
>>
>> I've been using MooseFS for several years and never had any problem
>> with it, even in very awkward situations. My feeling is that it is
>> really a rock-solid, battle-tested product.
>>
>> I gave LizardFS a try, mainly for erasure coding and high-
>> availability.
>> While the former worked as expected, the latter turned out to be a
>> myth: the free version of LizardFS does not provide more HA than
>> MooseFS CE: in both cases, building a HA solution requires writing
>> custom scripts and relying on a cluster managed such as corosync. I
>> see
>> no added value in using LizardFS for HA.
>>
>> On all other aspects, LizardFS does the same or worse than MooseFS. I
>> found performance to be roughly equivalent between the two (provided
>> you disable fsync on LizardFS chunkservers, where it is enabled by
>> default). Both solutions are still similar in many aspects, yet
>> LizardFS is clouded by a few negative points: ACLs are hardly usable,
>> custom goals are less powerful than storage classes and less
>> convenient
>> for geo-replication, FreeBSD support is inexistent, CLI tools are
>> less
>> efficient, and native NFS support is too young to be really usable.
>>
>> After a few months, I came to the conclusion than migrating to
>> LizardFS
>> was not worth the single erasure coding feature, especially now that
>> MooseFS 4.0 CE with EC is officially announced. I'd rather buy a few
>> more drives and cope with standard copies for a while than ditching
>> MooseFS reliability for LizardFS.
>>
>> Hope it helps,
>>
>> Marin
> A few corrections:
>
> 1. MooseFS Pro also includes a Windows client.
>
> 2. LizardFS did not "remove" tabs from the web UI: these tabs were
> added by MooseFS after LizardFS had forked the code base.
>