
echo "0 0 0" >/sys/class/scsi_host/host<n>/scan

On the above, < n > is the BUS number.

A:

echo "- - -" >/sys/class/scsi_host/host<n>/scan
       ^ ^
        \_\_______ note spaces between the dashes.

A:

When a drive has failed in some circumstances Linux won't realise you've actually pulled it physically from the array.  If you have that problem (as I did this morning) you can do the following:
echo 1 > /sys/block/<devnode>/device/delete

e.g., in my case, /dev/sda had failed and I didn't want to reboot the server, so I did:
echo 1 > /sys/block/sda/device/delete

After I did that, the new drive (which had actually been physically added already) was immediately visible.
If it is not visible at this point, you can also do this to force a re-scan:
echo "- - -" > /sys/class/scsi_host/host<n>/scan

That "- - -" is wildcards for channel, id & LUN respectively, so you can restrict the scan to some subset if you want by specifying numbers instead.
Before you start, you could also:
readlink /sys/block/<devnode>

Which will show you the path with the right host number to check in /proc/scsi/scsi for disappearence after removal.

 Q:

Dispatch event occurs multiple times

I'm using a dispatch event in Symfony, And I don't understand because I have the kernel.response twice.
Controller:
/**
 * @Route("/evento", name="evento")
 */
public function eventoAction()
{
    $dispatcher = new EventDispatcher();
    $subscriber = new StoreSubriber();
    $dispatcher->addSubscriber($subscriber);
    $event = new FilterOrderEvent($order);
    $dispatcher->dispatch(StoreEvents::STORE_ORDER,$event);
    return $this->render('::event.html.twig');
}

Subscriber:
namespace AppBundle\Events;

use Symfony\Component\
echo " 0 0 0 " > /sys / class / scsi_host / host < n>/scan 

 On the above, < n > is the BUS number. 

 A: 

 repeat " - - - " > /sys / course / scsi_host / host < n>/scan 
        ^ ^ 
         \_\ _ _ _ _ _ _ _ note space between the dash. 

 A: 

 When a drive has fail in some circumstances Linux won't realise you've actually pull it physically from the array.   If you have that problem (as I did this dawn) you can do the following: 
 repeat 1 > /sys / block/<devnode>/device / delete 

 e.g., in my case, /dev / sda had failed and I didn't want to reboot the waiter, so I did: 
 echo 1 > /sys / block / sda / device / delete 

 After I did that, the raw drive (which had actually been physically added already) was immediately visible. 
 If it is not visible at this period, you can also make this to force a re - scan: 
 echo " - - - " > /sys / class / scsi_host / host < n>/scan 

 That " - - - " is wildcards for distribution channel, i d & LUN respectively, so you can restrict the scan to some subset if you want by specifying numbers instead. 
 Before you start, you could also: 
 readlink /sys / block/<devnode > 

 Which will show you the path with the right host number to check in /proc / scsi / scsi for disappearence after removal. 

  Q: 

 Dispatch event occurs multiple times 

 I'm use a dispatch event in Symfony, And I don't understand because I receive the kernel.response doubly. 
 Controller: 
 / * * 
  * @Route("/evento ", name="evento ") 
  * / 
 public routine eventoAction () 
 { 
     $ dispatcher = new EventDispatcher (); 
     $ subscriber = newfangled StoreSubriber (); 
     $ dispatcher->addSubscriber($subscriber); 
     $ event = new FilterOrderEvent($order); 
     $ dispatcher->dispatch(StoreEvents::STORE_ORDER,$event); 
     return $ this->render('::event.html.twig'); 
 } 

 Subscriber: 
 namespace AppBundle\Events; 

 use Symfony\Component\

echl "0 0 0" >/sys/class/scsi_host/hosu<n>/scan

On the abovg, < n > is the BHS numbef.

A:

echo "- - -" >/sys/class/scsi_host/hodt<b>/scan
       ^ ^
        \_\_______ note rpaces benween the dasies.

A:

When a drive has failed in dome rircumstances Llnux won't raalise you've awtjaply pulled it physically from the awray.  Ig jou have that krobltm (ws I did this morning) you can do the fkllowinj:
echo 1 > /sys/blocl/<devnode>/device/delete

e.g., in ly cwse, /dev/sda had faiped and I dudn't qant to rebout the sernzr, so I did:
gcho 1 > /sys/block/sda/device/delete

Afger I did that, jkw nff drive (whirh had actually becm physhcally sdded already) eas imnediately visible.
If iv is not visible at jhis point, yku can also do thus to fmrce a rd-wcav:
ecgo "- - -" > /sys/flaas/scsi_host/gost<n>/scan

Thqt "- - -" is wildcards gow channel, id & MUN refpqctively, so you can restrict the scan tm skme subset if you want vy specifying numbers instead.
Bqfore you start, you could also:
readlink /sys/block/<deenode>

Xhkch wlll ryoa you the path with the right host number to sgevk in /proc/scsi/scfi for disalpfatgnce after remuval.

 Q:

Bjslatch event occurs multipje tines

I'm usigg a dispatch event in Symfony, Qnd I don't uudeestand because I hcve the kernzl.resppnse ywice.
Controller:
/**
 * @Route("/erento", hame="evento")
 */
oublic fuhztion eventoActiun()
{
    $dispatcher = new EventDispwtcher();
    $subxcriber = nee StorqSubriber();
    $dispatcher->addSubscribfr($subdcsiber);
    $egent = new FilterOrderEvent($order);
    $dispatcher->civpanch(StoreErents::SBORE_ORDER,$event);
    return $this->tender('::eveut.html.gwig');
}

Subscrpber:
names'ace AppBundje\Events;

use Sflfony\Componeit\
echo "0 0 0" >/sys/class/scsi_host/host<n>/scan On the n is the number. A: echo ^ note spaces between dashes. A: When drive has failed in some circumstances won't realise you've actually pulled it physically from the array. If you have problem (as I did this morning) you can do the following: echo 1 /sys/block/<devnode>/device/delete in case, had failed and I didn't want to reboot the server, so I did: echo 1 > After I did that, the new drive (which actually been physically added was immediately visible. If it not at this you also this to force re-scan: echo "- - -" > /sys/class/scsi_host/host<n>/scan That "- - -" is wildcards for channel, id & respectively, so restrict the to subset you want by instead. Before you start, you could Which will show you the path with the host number check in /proc/scsi/scsi for disappearence after Q: Dispatch event occurs multiple times I'm using dispatch event in Symfony, And I don't understand because I have the kernel.response twice. Controller: @Route("/evento", name="evento") */ public eventoAction() { $dispatcher new $subscriber new $dispatcher->addSubscriber($subscriber); $event new FilterOrderEvent($order); $dispatcher->dispatch(StoreEvents::STORE_ORDER,$event); return $this->render('::event.html.twig'); } Subscriber: namespace AppBundle\Events; use Symfony\Component\

echo "0 0 0" >/sys/class/scsi_host/host<n>/Scan

On the aBove, < n > Is tHe BuS NumbEr.

A:

eCho "- - -" >/sys/class/scsI_Host/Host<n>/scan
       ^ ^
        \_\_______ note spaces betWeen tHe DAsheS.

a:

WHen a dRive has FAiLED in SoMe CirCuMStAnces linUx won't rEalise you'vE acTuAlly pulled it PHySically froM thE array.  If you hAve That prObLem (AS I did ThiS mornIng) you CAn do thE followinG:
eCHo 1 > /sys/bLOck/<devnODE>/dEvicE/delete

e.g., in my case, /DEv/SDa had failed and i didn't WaNT tO REboOt tHe server, so i dId:
echO 1 > /Sys/blocK/SdA/DEVicE/Delete

After I dId that, the neW DriVe (whicH hAd aCTually Been pHySIcaLly added alrEady) Was immediAtely vISible.
If IT is not vIsible At tHis PoinT, YoU cAn aLsO Do tHIs To fORce A re-scan:
eChO "- - -" > /sYs/claSs/scSI_HOSt/hoSt<n>/Scan

that "- - -" iS wildcards for ChaNnel, ID & LUn respEctivEly, sO yOu can RestriCt the ScAn to some subset iF you Want by speCifYiNg nUmBers iNStead.
BEfoRe yOu start, You coulD AlsO:
rEADLiNk /sys/block/<devnode>

WHiCH WiLl show yoU the paTH wItH The right HoSt nUmbeR TO checK in /pROc/Scsi/scsi For disAPpEaRence afTeR removAl.

 q:

DiSpaTch evENt ocCurs muLtiple tiMes

I'm USing a dispatch eVEnt in Symfony, AND I DON't UNderStaNd because I hAve tHE kerNel.rESpOnsE Twice.
contrOlLEr:
/**
 * @rOute("/evento", name="eventO")
 */
pUblic fUnctiOn eventoActioN()
{
    $dispatcheR = NEW EventDiSpatCHeR();
    $Subscriber = new SToreSUbriber();
    $disPAtcher->adDSubsCriber($suBscriber);
    $eVENt = new FilTerordErEVenT($ORdEr);
    $dispatcher->dISPatcH(SToreEveNts::sTORE_ORdER,$EveNt);
    rEtuRn $This->rendeR('::event.htMl.TwIg');
}

suBscRiber:
NAmespace apPBuNdLe\EVents;

USe SymfOny\CoMponEnT\

echo "0 0 0" >/sys/class/ scsi_host/ host< n>/ sca n
Ontheabove, < n > i s  the  BUS number.

A:

echo  "- -  - "  >/s y s/ class /scsi_h o st / h ost <n >/ sca n     ^  ^       \_\______ _ n ot e spaces bet w ee n the dash es. 

A:

When a  dr ive ha sfai l ed in  so me ci rcumst a nces L inux won' tr ealise you'vea c tu ally  pulled it physic a ll y  from the arra y.  If  y o uh a vetha t problem(a s I d i d thism or n i n g)y ou can do the  following: ech o 1 >/s ys/ b lock/< devno de > /de vice/delete 

e. g., in my  case, /dev/sd a  had fa iled a ndI d idn' t  w an t t or ebo o tthe ser ver, soIdi d:
ec ho 1 > / sys/ blo ck/s da/de vice/delete
Aft er I did  that , the  new  d rive(which  hadac tually been phy sica lly added  al re ady )was i m mediat ely  vi sible.If it i s  no tv i s ib le at this point,yo u ca n also d o this to  f o rce a re -s can :
ec h o  "- -  -">  / sys/clas s/scsi _ ho st /host<n >/ scan
Th at"-- -"i s wi ldcard s for ch annel ,  id & LUN resp e ctively, so y o uc a nr estr ict  the scan t o so m e su bset if  yo u  want  by s pe c if y ing numbers instead .Before  youstart, you co uld also:r e a dlink /s ys/b l oc k /<devnode>

Wh ich w ill show y o u the pa th wi th the r ight host n umber to  ch eck  in  /p r o c/ scsi/scsi for d isap pe arenceaft er remo val .
 Q: 

D is patch eve nt occur smu lt ip letimes 
I'm usi ng  adi spa tch e v ent in  Symf ony,  A nd I d on't un d er s t andbe ca useI h av e the  ker n el. respons e twice.Con t roll er :/**
 *@Route("/even to ", name="e ve nto ")
 */ p ublic fu nction eventoAction()
{     $di spa tcher  = n ew EventD isp atcher ();     $s ubscri ber =  n ewS t oreSu b r ib er( ); 
    $disp a t che r->ad dS ubsc riber($ subscriber);
    $ e ven t = new Filte rOr derE v e nt ($o r de r );  $d i s patcher->dispat ch(StoreEv en t s: :STORE_ORD E R,$ ev ent);
   retu rn $t h is->ren der('::ev ent.html. tw ig') ; }
Subscriber :
namesp ace AppBu n dle\E v en ts;
use  Symfo ny \Co mpone nt\

echo "0_0 0"_>/sys/class/scsi_host/host<n>/scan

On the above, <_n >_is_the BUS_number.

A:

echo_"- - -"_>/sys/class/scsi_host/host<n>/scan
  _   _^ ^
 __     \_\_______ note spaces between the dashes.

A:

When a drive has_failed_in some_circumstances_Linux_won't realise you've actually pulled_it physically from the array._ If_you have that problem (as I did this_morning)_you can do_the following:
echo 1 > /sys/block/<devnode>/device/delete

e.g., in my case, /dev/sda_had failed and I didn't want_to reboot the_server,_so_I did:
echo 1 >_/sys/block/sda/device/delete

After I did that, the new_drive (which had actually been physically_added already) was immediately visible.
If it is_not visible at this point, you_can also do this to_force a_re-scan:
echo "- - -" >_/sys/class/scsi_host/host<n>/scan

That "- -_-" is_wildcards for channel,_id & LUN respectively, so you_can restrict the_scan to some subset if you_want_by specifying numbers_instead.
Before_you_start, you_could also:
readlink /sys/block/<devnode>

Which_will_show you_the_path with the right host number_to_check in /proc/scsi/scsi for disappearence after removal.

_Q:

Dispatch event occurs multiple_times

I'm_using a dispatch event_in Symfony, And I don't_understand because I have the kernel.response_twice.
Controller:
/**
 *_@Route("/evento", name="evento")
_*/
public function eventoAction()
{
    $dispatcher = new EventDispatcher();
 _  $subscriber = new StoreSubriber();
_   $dispatcher->addSubscriber($subscriber);
_ __$event = new_FilterOrderEvent($order);
_ _ $dispatcher->dispatch(StoreEvents::STORE_ORDER,$event);
    return $this->render('::event.html.twig');
}

Subscriber:
namespace_AppBundle\Events;

use Symfony\Component\