Hi Kurt,

AFAIK when you set active=0 on the MDS it means "don't write new files to this OST but still read files". If what you really want is "don't try to read files from this OST", then you have to flip the active=0 bit on all your clients. I've never used the llite.lazystatfs option but it may do the same thing.

FWIW, an alternative command to deactivate an OST is command "lctl --device=XX deactivate".

regards,
chris hunter


On 01/21/2016 01:09 PM, Kurt Strosahl wrote:
Good Afternoon Chris,

    I have already run the active=0 command on the mds, is there another step?  
From my testing under 2.5.3 the clients will hang indefinitely without using 
the lazystatfs=1.

    Our major issue at present is that when the OST died it had a fair amount 
of data on in (closing in on 2M files lost), and it seems like the client gets 
into a bad state when calls re made repeatedly to files that are lost (but 
still have their ost index information).  As the crawl has unlinked files the 
number of errors has dropped, as have client crashes.

w/r,
Kurt

----- Original Message -----
From: "Chris Hunter" <chunt...@gmail.com>
To: lustre-discuss@lists.lustre.org
Cc: "Kurt Strosahl" <stros...@jlab.org>
Sent: Thursday, January 21, 2016 12:50:03 PM
Subject: [lustre-discuss] Inactivated ost still showing up on the mds

Hi Kurt,
For reference when an underlying OST object is missing, this is the
error message generated on our MDS (lustre 2.5):
Lustre: 12752:0:(mdd_object.c:1983:mdd_dir_page_build()) build page failed: -5!

I suspect until you update the MGS info the MDS will still connect to
the deactive OST.

My experience is sometimes the recipe to deactivate an OST works
flawlessly sometimes other times the clients hang on "df" command and
timeout on file access. I guess the order which you run the commands
(ie. client vs server) is important.

regards,
chris hunter

From: Kurt Strosahl <stros...@jlab.org>
To: lustre-discuss@lists.lustre.org
Subject: [lustre-discuss] Inactivated ost still showing up on the mds

All,

    Continuing the issues that I reported yesterday...  I found that by 
unlinking lost files that I was able to stop the below error from occurring, 
this gives me hope that systems will stop crashing once all the lost files are 
scrubbed.

LustreError: 7676:0:(sec.c:379:import_sec_validate_get()) import 
ffff880623098800 (NEW) with no sec
LustreError: 7971:0:(sec.c:379:import_sec_validate_get()) import 
ffff880623098800 (NEW) with no sec

    I do note that the inactivated ost doesn't seem to ever REALLY go away.  
After I removed an ost from my test system I noticed that the mds still showed 
it...

On a client hooked up to the test system...
client: lfs df
UUID                   1K-blocks        Used   Available Use% Mounted on
testL-MDT0000_UUID    1819458432       10112  1819446272   0% /testlustre[MDT:0]
testL-OST0000_UUID   57914433152       12672 57914418432   0% /testlustre[OST:0]
testL-OST0001_UUID   57914433408       12672 57914418688   0% /testlustre[OST:1]
testL-OST0002_UUID   57914433408       12672 57914418688   0% /testlustre[OST:2]
OST0003             : inactive device
testL-OST0004_UUID   57914436992      144896 57914290048   0% /testlustre[OST:4

on the mds it still shows as up when I do lctl dl:
mds: lctl dl | grep OST0003
  22 UP osp testL-OST0003-osc-MDT0000 testL-MDT0000-mdtlov_UUID 5

So I stopped the test system, ran lctl dl again (getting no results), and 
restarted it.  Once the system was back up I still saw OST3 marked as UP with 
lctl dl:
mds: lctl dl | grep OST0003
  11 UP osp testL-OST0003-osc-MDT0000 testL-MDT0000-mdtlov_UUID 5

Why does the mds still think that this OST is up?



_______________________________________________
lustre-discuss mailing list
lustre-discuss@lists.lustre.org
http://lists.lustre.org/listinfo.cgi/lustre-discuss-lustre.org

Reply via email to