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New Contributor
Posts: 4
Registered: ‎09-23-2013

Access Gateway mode question

Hello,

I am about to connect a new blade center server to an existing fabric composed of 2 48000 switches at terget release.

I want to configure the new embedded brocade switches (model 72.3) in access gateway mode to simplify management and connect 2 cables to the core switch.

What i do not understand is if i need to configure something about port mapping in the access gateway switch and if there is any behaviour difference when you lose an ISL vs when you lose a connection in access gateway mode.

The bladecenter switch comes already configured with PG0 containing all N-Ports and all F-Ports mapped to this group and automatic device load balancing is disabled.

Here is the configuration display.

sanswalfa:admin> ag --pgshow

PG_ID   PG_Name PG_Mode         N_Ports         F_Ports

----------------------------------------------------------------------------------------

0       pg0     -              0;17;18;19;20;   1;2;3;4;5;6;7;8;9;10;11;12;13;14;15;16;

                        21;22;23

----------------------------------------------------------------------------------------

sanswalfa:admin> ag --policyshow

AG Policy                        Policy Name     State

----------------------------------------------------------

Port Grouping                    pg              Enabled

Auto Port Configuration          auto            Disabled

Advanced Device Security         ads             Disabled

WWN Based Load Balancing         wwnloadbalance          Disabled

----------------------------------------------------------

sanswalfa:admin> ag --mapshow

N_Port  Configured_F_Ports      Current_F_Ports Failover Failback PG_ID PG_Name

--------------------------------------------------------------------------------

   0    15;16                   None             1       1         0    pg0

  17    1;2                     None             1       1         0    pg0

  18    9;10                    None             1       1         0    pg0

  19    3;4                     None             1       1         0    pg0

  20    11;12                   None             1       1         0    pg0

  21    5;6                     None             1       1         0    pg0

  22    13;14                   None             1       1         0    pg0

  23    7;8                     1;2              1       1         0    pg0

--------------------------------------------------------------------------------

:admin> switchshow

switchName:     sanswalfa

switchType:     72.3

switchState:    Online

switchMode:     Access Gateway Mode

switchWwn:      XXXXXX

switchBeacon:   OFF

Index Port Address Media Speed State     Proto

==============================================

  0   0   290000   id    N4   Online      FC  N-Port  xxx:XX:XX

  1   1   290100   cu    N8   Online      FC  F-Port  xxx:XX:XX

  2   2   290200   cu    N8   Online      FC  F-Port  xxx:XX:XX

  3   3   290300   cu    AN   No_Sync     FC

  4   4   290400   cu    AN   No_Sync     FC

  5   5   290500   cu    AN   No_Sync     FC  Disabled (Persistent)

  6   6   290600   cu    AN   No_Sync     FC

  7   7   290700   cu    AN   No_Sync     FC

  8   8   290800   cu    AN   No_Sync     FC

  9   9   290900   cu    AN   No_Sync     FC

10  10   290a00   cu    AN   No_Sync     FC  Disabled (Persistent)

11  11   290b00   cu    AN   No_Sync     FC

12  12   290c00   cu    AN   No_Sync     FC  Disabled (Persistent)

13  13   290d00   cu    AN   No_Sync     FC

14  14   290e00   cu    AN   No_Sync     FC  Disabled (Persistent)

15  15   290f00   cu    AN   No_Sync     FC

16  16   291000   cu    AN   No_Sync     FC  Disabled (Persistent)

17  17   291100   --    N8   No_Module   FC

18  18   291200   --    N8   No_Module   FC

19  19   291300   --    N8   No_Module   FC

20  20   291400   --    N8   No_Module   FC

21  21   291500   --    N8   No_Module   FC

22  22   291600   --    N8   No_Module   FC

23  23   291700   id    N4   Online      FC  N-Port  xxxxxxx

Is this configuration ok? Do i need to change anything?

Thanks in advance

Guido

Valued Contributor
Posts: 931
Registered: ‎12-30-2009

Re: Access Gateway mode question

Here is a copy of the admin guide for access gateway

http://www.brocade.com/downloads/documents/product_manuals/B_SAN/AccessGateway_AdminGd_v700.pdf

Have a read there's a lot of stuff in there.

As for your questions;

What i do not understand is if i need to configure something about port mapping in the access gateway switch

In a two link setup you do need to change the map.

sanswalfa:admin> ag --mapshow

N_Port  Configured_F_Ports      Current_F_Ports Failover Failback PG_ID PG_Name

--------------------------------------------------------------------------------

   0    15;16                   None             1       1         0    pg0

  17    1;2                     None             1       1         0    pg0

  18    9;10                    None             1       1         0    pg0

  19    3;4                     None             1       1         0    pg0

  20    11;12                   None             1       1         0    pg0

  21    5;6                     None             1       1         0    pg0

  22    13;14                   None             1       1         0    pg0

  23    7;8                     1;2              1       1         0    pg0

--------------------------------------------------------------------------------

This shows you the current map were 2 internal port (ie facing the blades) or mapped against 1 external port (the one providing the uplink).

Its best to alter this according your layout.

if there is any behaviour difference when you lose an ISL vs when you lose a connection in access gateway mode.

Yes there's a difference, a ISL refers to inter switch connectivity (E ports). As your bladecenter switch is (to be) configured as an AG, fabric services that a regular switch provides are disabled. As such the device only support F (server facing) and N ports (fabric facing). If you setup your maps and failover/back options if there is any behaviour difference when you lose an ISL vs when you lose a connection in access gateway mode.with 2 links to the fabric a link failure on the functional level looks the same a an ISL failure (ie traffic will be routed to the working link).

One major difference with AG mode versus switch mode is that in AG mode an link failover will change FCID, you should plan accordingly

But like i said read the admin guide, all information to your question and follow up questions are in there in great detail

New Contributor
Posts: 4
Registered: ‎09-23-2013

Re: Access Gateway mode question

What i do not understand is if i need to configure something about port mapping in the access gateway switch

In a two link setup you do need to change the map.

sanswalfa:admin> ag --mapshow

N_Port  Configured_F_Ports      Current_F_Ports Failover Failback PG_ID PG_Name

--------------------------------------------------------------------------------

   0    15;16                   None             1       1         0    pg0

  17    1;2                     None             1       1         0    pg0

  18    9;10                    None             1       1         0    pg0

  19    3;4                     None             1       1         0    pg0

  20    11;12                   None             1       1         0    pg0

  21    5;6                     None             1       1         0    pg0

  22    13;14                   None             1       1         0    pg0

  23    7;8                     1;2              1       1         0    pg0

--------------------------------------------------------------------------------

This shows you the current map were 2 internal port (ie facing the blades) or mapped against 1 external port (the one providing the uplink).

Its best to alter this according your layout.

Ok i saw that both F-Ports were mapping to only one N-Port so i asked.

I have already looked at the manual you linked here but i cannot understand which configuration is the best to achieve an even wwpn distribution on N-Ports, automatic device load balancing seems the way to go but if i understood it right it may move wwpn from one N-port to another, even if there are no failures, causing the link to go briefly down and an fcid change.

Is there a way to configure port mappings so wwpns get distributed evenly on N-Ports without having to configure it manually every time they come online?

Thanks for your answe

Guido

Valued Contributor
Posts: 931
Registered: ‎12-30-2009

Re: Access Gateway mode question

automatic device load balancing seems the way to go but if i understood it right it may move wwpn from one N-port to another, even if there are no failures, causing the link to go briefly down and an fcid change.

If you're refering to APC, then I read something different and wwpn don't move unless they logout and back in again or a failure occurs. That said APC gives you no control

If you meant "Automatic Login Balancing mode" as part of the Port Grouping policies then wwpn will be redistributed as links and server come online or disappear. There is some degree of control as you can disable the rebalance feature.

Is there a way to configure port mappings so wwpns get distributed evenly on N-Ports without having to configure it manually every time they come online?

Perhaps an PG with ALB set but a disabled rebalance feature is what you're looking for.

If not a manual map with half of your internal F ports mapped against one N port and the other half of your F ports to the other N port would create a similar setup. You would have to check/alter the failover and failback settings according to your needs.

New Contributor
Posts: 4
Registered: ‎09-23-2013

Re: Access Gateway mode question

dion.v.d.c ha scritto:

automatic device load balancing seems the way to go but if i understood it right it may move wwpn from one N-port to another, even if there are no failures, causing the link to go briefly down and an fcid change.

If you're refering to APC, then I read something different and wwpn don't move unless they logout and back in again or a failure occurs. That said APC gives you no control

If you meant "Automatic Login Balancing mode" as part of the Port Grouping policies then wwpn will be redistributed as links and server come online or disappear. There is some degree of control as you can disable the rebalance feature.

Is there a way to configure port mappings so wwpns get distributed evenly on N-Ports without having to configure it manually every time they come online?

Perhaps an PG with ALB set but a disabled rebalance feature is what you're looking for.

If not a manual map with half of your internal F ports mapped against one N port and the other half of your F ports to the other N port would create a similar setup. You would have to check/alter the failover and failback settings according to your needs.

Maybe APC is just what i want, it will distribute evenly all initiators and provide handsfree operation.

I'll try it and see how it goes with a few tests.

Thanks

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