shmget and vimage

[Bjoern A. Zeeb]

On Tue, 16 Mar 2010, Milan Obuch wrote:

> On Tuesday 16 March 2010 14:55:43 Milan Obuch wrote:
>> Hi,
>>
>> some time ago I built a multi network monitor using older version with
>> Marko Zec's vimage patch. I am trying to port it to 8-STABLE (newer
>> features, easier maintenance...) with partial success.
>>
>> Basically, I use shared memory as common data area across more vimages in
>> order to be able to generate quick summaries from in-memory data. I was not
>> able to get it running under freshly compiler 8-STABLE, error message is
>>
>> shmget: Function not implemented
>>
>> Has anybody any idea? Patch to test to enable use of shared memory in vnet
>> jails?
>>
>> Regards,
>> Milan
>>
>
> Forget to add...
>
> In my code, I use
>
> if ((shmid = shmget(shmkey,sizeof(mdc),IPC_CREAT | 0640)) == -1)
>  err(1,"shmget");
>
> to create a shared segment and
>
> if ((shmid = shmget(shmkey,sizeof(mdc),0)) == -1)
>  err(1,"shmget");
>
> to get an id for already created segment.
>
> Both are failing under non-root vimage jail, but it works under main host. At
> first I thought shared memory is not yet virtualized, but ipcs display
> existing segments in both root/main host and vnet jail.ipcrm, however, works
> only in non-jailed host...
>
> ipcrm: shmid(131072): : Function not implemented

if you create a jail with a vnet you want to give it
 	jail - i -c vnet allow.sysvipc ..

and then things should start to work at leat in the non-virtualized
way (global namespace across all jails).

/bz

-- 
Bjoern A. Zeeb         It will not break if you know what you are doing.