Re: iSCSI: Aggregation tags in SendTargets

[Mark Bakke <mbakke@cisco.com>]

Marjorie-

You are right; I meant alpha-numeric.  Again, if nobody really
needs them, we can stick with numeric tags.

--
Mark

"KRUEGER,MARJORIE (HP-Roseville,ex1)" wrote:
> 
> I think you meant to ask
> 
> ***    Anyone need Alpha-Numeric Aggregation Tags    ***
>                    ^^^^^
>                    Going once....
> 
> I have no strong opinion either.  Alpha's a little more user-friendly, but
> that is not important enough in this feature to warrant any argument, so if
> implementors want numeric tags, let them be numeric...
> 
> Marj
> 
> > -----Original Message-----
> > From: Mark Bakke [mailto:mbakke@cisco.com]
> > Sent: Wednesday, May 16, 2001 9:13 AM
> > To: Kevin Gibbons
> > Cc: IPS; Marjorie Krueger
> > Subject: Re: iSCSI: Aggregation tags in SendTargets
> >
> >
> > Kevin-
> >
> > I think that a numeric tag would be simpler as you had said.
> > Marjorie had asked for the alpha-numeric tag; anyone needing
> > more than a numeric tag, please speak up.  I don't have any
> > particular opinion either way.
> >
> > If nobody requires alpha-numeric tags, I will change it to
> > a simple numeric tag.  Otherwise, I'll update the examples.
> >
> > So,
> >
> >    ***    Anyone need Numeric Aggregation Tags    ***
> >
> >                    Going once....
> >
> > --
> > Mark
> >
> > Kevin Gibbons wrote:
> > >
> > > Mark,
> > >         in the proposed change to the NDT document, you
> > state that the
> > > aggregation "tag" is an ASCII, alpha-numeric string.  I
> > read this to mean
> > > the tag can be any string value.
> > >
> > >         Could you make the aggregation tag be a numeric
> > string, indicating
> > > an aggregation group?  This would align with your example,
> > and should make
> > > it easier to quickly index portals into different groups.
> > >
> > >         Regards, Kevin
> > >
> > > -----Original Message-----
> > > From: Mark Bakke [mailto:mbakke@cisco.com]
> > > Sent: Tuesday, May 15, 2001 1:06 PM
> > > To: IPS
> > > Subject: iSCSI: Aggregation tags in SendTargets
> > >
> > > During the interim meeting, we had discussed a proposal to
> > > add an aggregation tag to the SendTargets response, indicating
> > > which (if any) target addresses supported multiple connections
> > > per session, and which groups of addresses an initiator could
> > > hope to aggregate a session across.
> > >
> > > Aggregation tags were generally well-received; a small modification
> > > to the proposed method also allows an initiator to know whether
> > > a single address supports multiple connections per session just
> > > by itself.
> > >
> > > Here is the section that would go into the NDT document.
> > >
> > > --
> > >
> > > (This would be added to section 4.2, right before the
> > vendor-specific
> > > paragraph at the end):
> > >
> > >   If an iSCSI target supports multiple connections per session,
> > >   it must indicate this by including an aggregation tag after each
> > >   address, in the form of
> > >
> > >     TargetAddress=address,tag
> > >
> > >   Where "tag" is an ASCII, alpha-numeric string indicating
> > an address
> > >   group.  Within a single session, a connection may be
> > requested to any
> > >   combination of TCP addresses that have the same tag.  If
> > an address
> > >   supports multiple connections per session, but does not support
> > >   spanning a session across other addresses, it will have its own
> > >   tag.
> > >
> > >   Here is an example:
> > >
> > >     TargetName=fqn.com.acme.diskarray.sn.8675309
> > >     TargetAddress=10.1.0.45:3000,1
> > >     TargetAddress=10.1.1.46:3000,1
> > >     TargetAddress=10.1.0.47:3000,2
> > >     TargetAddress=10.1.1.48:3000,2
> > >     TargetAddress=10.1.1.49:3000
> > >     TargetAddress=10.1.1.50:3000,3
> > >     TargetAlias=Oracle tables
> > >
> > >   In this example, any of the target addresses can be used to reach
> > >   the same target.  A single-connection session can be established
> > >   to any of these TCP addresses.  A multiple-connection
> > session could span
> > >   addresses .45 and .46, or .47 and .48, but cannot span any other
> > >   combination.  A TargetAddress without a tag (.49) cannot
> > be combined
> > >   with any other address within the same session.  A TargetAddress
> > >   with a tag that is not shared with other addresses
> > supports multiple
> > >   connections per session, but all connections must be to the same
> > >   address.
> > >
> > >   To make this work, there are a few rules to follow:
> > >
> > >   A target that does not support spanning sessions across
> > multiple addresses
> > >   MUST NOT include the tags.
> > >
> > >   A target that is accessible via multiple TCP addresses
> > SHOULD include
> > >   all TCP addresses in a SendTargets response.
> > >
> > >   A target with multiple TCP addresses that supports a
> > session spanning
> > >   multiple TCP addresses MUST indicate TCP address groups
> > using aggregation
> > >   tages in a SendTargets response.
> > >
> > >   Aggregation tags have no meaning or persistence beyond a
> > particular
> > >   SendTargets response.
> > >
> > > --
> > > Mark A. Bakke
> > > Cisco Systems
> > > mbakke@cisco.com
> > > 763.398.1054
> 

-- 
Mark A. Bakke
Cisco Systems
mbakke@cisco.com
763.398.1054