Howto: 50Gb tri-speed transceivers

Overview

HPE Aruba Networking recently released a major new firmware upgrade for CX switches with CX 10.12. One of the interesting new features is that the standard 50Gb multimode transceiver has been enabled with tri-speed mode. That's right, if you already have a R0M48A 50Gb transceiver, when you use it in switch with CX 10.12, you can run at 10, 25 or 50Gb speeds!

I will show how to do an upgrade from 10 to 25 to 50Gb with minimal downtime in this post. 

Scenario

This could be useful in scenarios such as:

• You upgrade core/aggregation switches first (eg with the CX 8360, CX 6400 models with 50Gb ports) but still need to connect to the 10Gb downstream access switches: put in 50Gb optics and run them at 10Gb until  you can upgrade the access switches
• Conversely, the access switches have been replaced with CX6300, and you want to run 25 or 50Gb uplinks, but the upstream core/agg devices only have 10 or 25Gb ports still: include 50Gb optics in the 6300 access switches and run them at the lower speed until  you can upgrade the core/agg switches

Example Step Upgrade Process

Environment

• 2 x 6300 24 port switches
• The upper switch is 6300-aggregation
• The lower switch is 6300-access
• Both switches have a pair of SFP56 ports configured as an LACP LAG (1/1/27 & 1/1/28)

In the starting configuration, the aggregation switch has an LACP LAG group running over a pair of 50Gb tri-speed transceivers configured to run at 10Gb, connected to the access switch with a pair of 10Gb transceivers.

Aggregation Switch Config

interface lag 1    description Downstream Lag    no shutdown    no routing    vlan trunk native 930    vlan trunk allowed all    lacp mode active    lacp fallback-static    lacp rate fast    exitinterface 1/1/27    no shutdown    speed auto 10g        ! actual speed 10g    lag 1    exitinterface 1/1/28    no shutdown    speed auto 10g        ! actual speed 10g    lag 1    exit

Access Switch Config

interface lag 1    description Uplink-Lag    no shutdown    no routing    vlan trunk native 930    vlan trunk allowed all    dhcpv4-snooping trust    lacp mode active    lacp rate fast    exitinterface 1/1/27    no shutdown    lag 1    exitinterface 1/1/28    no shutdown    lag 1    exit

Central, MultiEdit and LACP

• If you are managing these switches with Central, it is best to use MultiEdit to make these changes.
• Using the Central GUI may be challenging because you can't modify LAG member speed individually.
• You can use the CLI too, but note that after release 2.5.9, Central will overwrite changes made in support mode, so you will have to complete the whole task in less time that it takes Central to identify the changes and change them back.
• It is also important to have a loop avoidance mechanism in place. I have MSTP (basic settings as provided by the Central GUI).
  Remember that speeds cannot be mixed in a LAG - all members must be the same speed, so you cannot add a 25Gb member to a 10Gb LAG.

Upgrade from 10Gb to 25Gb

1. On agg switch, edit config for first port (1/1/27): shutdown; speed auto 25g
2. On access switch, swap in 25Gb transceiver first port (1/1/27)
   At this stage, the LAG will be active on one link only at 10Gb still
   
   
    
3. On agg switch, edit config to re-enable first port (1/1/27): no shutdown
   & edit config for second port (1/1/28): shutdown; speed auto 25g; remove from lag
   There will be some disruption here as the LAG changes from 10 to 25Gb; I usually see about 18 x 1s pings dropped.
   LAG is now up with single 25Gb member
4. On access switch, swap in 25Gb transceiver to second port (1/1/28)
5. On agg switch, edit config for second port (1/1/28): no shutdown; lag 1
   Now there is a LAG with 2 x 25Gb members.
   
   
   
    

Next step is 25 to 50Gb

The process is essentially the same again.

1. On agg switch, edit config for first port (1/1/27): shutdown; remove speed setting (default is 50Gb)
2. On access switch, swap in 50Gb transceiver first port (1/1/27)
3. On agg switch, edit config to re-enable first port (1/1/27): no shutdown
   & edit config for second port (1/1/28): shutdown; remove speed; remove from lag
   There will be some disruption here as the LAG changes from 25 to 50Gb; I usually see about 18 x 1s pings dropped.
   LAG is now up with single 50Gb member
4. On access switch, swap in 50Gb transceiver to second port (1/1/28)
5. On agg switch, edit config for second port (1/1/28): no shutdown; lag 1
   Now there is a LAG with 2 x 50Gb members.
   
   
   
    

Q&A

Q: What speeds does the tri-speed R0M48A transceiver support?
A: 10, 25 or 50Gb

Q: Will the tri-speed R0M48A run in any port?
A: It will run only in SFP56 ports. These are found in the 6300, 6400, 8360 series of CX switches. IRIS can help you configure the correct transceivers for  switches, along with the Transceiver Guide.
The output below is from a CX 6200 switch - it only has 10Gb SFP+ ports (not SFP56 like the 6300), and the 50Gb transceiver is specifically flagged as incompatible.

6200F-12# sh int 1/1/15 transceiver------------------------------------------------------------------------------Port           Type             Product          Serial           Part                                Number           Number           Number------------------------------------------------------------------------------1/1/15         50G-SR           R0M48A           MYxxxxxxxx       1990-48036200F-12# sh int 1/1/15 transceiver detailTransceiver in 1/1/15 Interface Name      : 1/1/15 Type                : 50G-SR / 50G SFP56 SR Connector Type      : LC Transceiver Status  : An HPE pluggable module that is incompatible with this interface Wavelength          : 850nm Transfer Distance   : 0.00km (SMF), 0m (OM1), 0m (OM2), 70m (OM3) Diagnostic Support  : None Product Number      : R0M48A Serial Number       : MYxxxxxxxx Part Number         : 1990-4803

Q: Is the tri-speed R0M48A auto-sensing?
A: No, it defaults to 50Gb, so you must specify 10 or 25Gb.

References

https://asp.arubanetworks.com/downloads;search=transceiver;sort=RELEASEDATE_DESC;fileTypes=DOCUMENT;products=Aruba%20Switches
AOS-Switch and AOS-CX Transceiver Guide

https://community.arubanetworks.com/viewdocument/aos-cx-1012-software-release-ente
AOS-CX 10.12 Training Materials

------------------------------
Richard Litchfield
Airheads MVP 2020, 2021, 2022
------------------------------

From the Datasheet: DS_6300Series.pdf,:

• (note 1). 50G capability is for use with 50G DACs for both interconnect and VSF stacking

Is this not the case anymore ?

------------------------------
Steinar

Original Message:
Sent: Sep 30, 2023 10:49 AM
From: Richard Litchfield
Subject: Howto: 50Gb tri-speed transceivers

Howto: 50Gb tri-speed transceivers

Overview

HPE Aruba Networking recently released a major new firmware upgrade for CX switches with CX 10.12. One of the interesting new features is that the standard 50Gb multimode transceiver has been enabled with tri-speed mode. That's right, if you already have a R0M48A 50Gb transceiver, when you use it in switch with CX 10.12, you can run at 10, 25 or 50Gb speeds!

I will show how to do an upgrade from 10 to 25 to 50Gb with minimal downtime in this post. 

Scenario

This could be useful in scenarios such as:

• You upgrade core/aggregation switches first (eg with the CX 8360, CX 6400 models with 50Gb ports) but still need to connect to the 10Gb downstream access switches: put in 50Gb optics and run them at 10Gb until  you can upgrade the access switches
• Conversely, the access switches have been replaced with CX6300, and you want to run 25 or 50Gb uplinks, but the upstream core/agg devices only have 10 or 25Gb ports still: include 50Gb optics in the 6300 access switches and run them at the lower speed until  you can upgrade the core/agg switches

Example Step Upgrade Process

Environment

• 2 x 6300 24 port switches
• The upper switch is 6300-aggregation
• The lower switch is 6300-access
• Both switches have a pair of SFP56 ports configured as an LACP LAG (1/1/27 & 1/1/28)

In the starting configuration, the aggregation switch has an LACP LAG group running over a pair of 50Gb tri-speed transceivers configured to run at 10Gb, connected to the access switch with a pair of 10Gb transceivers.

Aggregation Switch Config

interface lag 1    description Downstream Lag    no shutdown    no routing    vlan trunk native 930    vlan trunk allowed all    lacp mode active    lacp fallback-static    lacp rate fast    exitinterface 1/1/27    no shutdown    speed auto 10g        ! actual speed 10g    lag 1    exitinterface 1/1/28    no shutdown    speed auto 10g        ! actual speed 10g    lag 1    exit

Access Switch Config

interface lag 1    description Uplink-Lag    no shutdown    no routing    vlan trunk native 930    vlan trunk allowed all    dhcpv4-snooping trust    lacp mode active    lacp rate fast    exitinterface 1/1/27    no shutdown    lag 1    exitinterface 1/1/28    no shutdown    lag 1    exit

Central, MultiEdit and LACP

• If you are managing these switches with Central, it is best to use MultiEdit to make these changes.
• Using the Central GUI may be challenging because you can't modify LAG member speed individually.
• You can use the CLI too, but note that after release 2.5.9, Central will overwrite changes made in support mode, so you will have to complete the whole task in less time that it takes Central to identify the changes and change them back.
• It is also important to have a loop avoidance mechanism in place. I have MSTP (basic settings as provided by the Central GUI).
  Remember that speeds cannot be mixed in a LAG - all members must be the same speed, so you cannot add a 25Gb member to a 10Gb LAG.

Upgrade from 10Gb to 25Gb

1. On agg switch, edit config for first port (1/1/27): shutdown; speed auto 25g
2. On access switch, swap in 25Gb transceiver first port (1/1/27)
   At this stage, the LAG will be active on one link only at 10Gb still
   
   
    
3. On agg switch, edit config to re-enable first port (1/1/27): no shutdown
   & edit config for second port (1/1/28): shutdown; speed auto 25g; remove from lag
   There will be some disruption here as the LAG changes from 10 to 25Gb; I usually see about 18 x 1s pings dropped.
   LAG is now up with single 25Gb member
4. On access switch, swap in 25Gb transceiver to second port (1/1/28)
5. On agg switch, edit config for second port (1/1/28): no shutdown; lag 1
   Now there is a LAG with 2 x 25Gb members.
   
   
   
    

Next step is 25 to 50Gb

The process is essentially the same again.

1. On agg switch, edit config for first port (1/1/27): shutdown; remove speed setting (default is 50Gb)
2. On access switch, swap in 50Gb transceiver first port (1/1/27)
3. On agg switch, edit config to re-enable first port (1/1/27): no shutdown
   & edit config for second port (1/1/28): shutdown; remove speed; remove from lag
   There will be some disruption here as the LAG changes from 25 to 50Gb; I usually see about 18 x 1s pings dropped.
   LAG is now up with single 50Gb member
4. On access switch, swap in 50Gb transceiver to second port (1/1/28)
5. On agg switch, edit config for second port (1/1/28): no shutdown; lag 1
   Now there is a LAG with 2 x 50Gb members.
   
   
   
    

Q&A

Q: What speeds does the tri-speed R0M48A transceiver support?
A: 10, 25 or 50Gb

Q: Will the tri-speed R0M48A run in any port?
A: It will run only in SFP56 ports. These are found in the 6300, 6400, 8360 series of CX switches. IRIS can help you configure the correct transceivers for  switches, along with the Transceiver Guide.
The output below is from a CX 6200 switch - it only has 10Gb SFP+ ports (not SFP56 like the 6300), and the 50Gb transceiver is specifically flagged as incompatible.

6200F-12# sh int 1/1/15 transceiver------------------------------------------------------------------------------Port           Type             Product          Serial           Part                                Number           Number           Number------------------------------------------------------------------------------1/1/15         50G-SR           R0M48A           MYxxxxxxxx       1990-48036200F-12# sh int 1/1/15 transceiver detailTransceiver in 1/1/15 Interface Name      : 1/1/15 Type                : 50G-SR / 50G SFP56 SR Connector Type      : LC Transceiver Status  : An HPE pluggable module that is incompatible with this interface Wavelength          : 850nm Transfer Distance   : 0.00km (SMF), 0m (OM1), 0m (OM2), 70m (OM3) Diagnostic Support  : None Product Number      : R0M48A Serial Number       : MYxxxxxxxx Part Number         : 1990-4803

Q: Is the tri-speed R0M48A auto-sensing?
A: No, it defaults to 50Gb, so you must specify 10 or 25Gb.

References

https://asp.arubanetworks.com/downloads;search=transceiver;sort=RELEASEDATE_DESC;fileTypes=DOCUMENT;products=Aruba%20Switches
AOS-Switch and AOS-CX Transceiver Guide

https://community.arubanetworks.com/viewdocument/aos-cx-1012-software-release-ente
AOS-CX 10.12 Training Materials

------------------------------
Richard Litchfield
Airheads MVP 2020, 2021, 2022
------------------------------

DACs are still supported, and make most sense for stacking within a rack or cabinet.

The 50Gb transceivers are useful for high-speed uplinks, but you could also use them for stacking: this could be useful when the switches are separated by a distance longer than a DAC supports.

From the Datasheet: DS_6300Series.pdf,:

• (note 1). 50G capability is for use with 50G DACs for both interconnect and VSF stacking

Is this not the case anymore ?

------------------------------
Steinar

Original Message:
Sent: Sep 30, 2023 10:49 AM
From: Richard Litchfield
Subject: Howto: 50Gb tri-speed transceivers

Howto: 50Gb tri-speed transceivers

Overview

HPE Aruba Networking recently released a major new firmware upgrade for CX switches with CX 10.12. One of the interesting new features is that the standard 50Gb multimode transceiver has been enabled with tri-speed mode. That's right, if you already have a R0M48A 50Gb transceiver, when you use it in switch with CX 10.12, you can run at 10, 25 or 50Gb speeds!

I will show how to do an upgrade from 10 to 25 to 50Gb with minimal downtime in this post. 

Scenario

This could be useful in scenarios such as:

• You upgrade core/aggregation switches first (eg with the CX 8360, CX 6400 models with 50Gb ports) but still need to connect to the 10Gb downstream access switches: put in 50Gb optics and run them at 10Gb until  you can upgrade the access switches
• Conversely, the access switches have been replaced with CX6300, and you want to run 25 or 50Gb uplinks, but the upstream core/agg devices only have 10 or 25Gb ports still: include 50Gb optics in the 6300 access switches and run them at the lower speed until  you can upgrade the core/agg switches

Example Step Upgrade Process

Environment

• 2 x 6300 24 port switches
• The upper switch is 6300-aggregation
• The lower switch is 6300-access
• Both switches have a pair of SFP56 ports configured as an LACP LAG (1/1/27 & 1/1/28)

In the starting configuration, the aggregation switch has an LACP LAG group running over a pair of 50Gb tri-speed transceivers configured to run at 10Gb, connected to the access switch with a pair of 10Gb transceivers.

Aggregation Switch Config

interface lag 1    description Downstream Lag    no shutdown    no routing    vlan trunk native 930    vlan trunk allowed all    lacp mode active    lacp fallback-static    lacp rate fast    exitinterface 1/1/27    no shutdown    speed auto 10g        ! actual speed 10g    lag 1    exitinterface 1/1/28    no shutdown    speed auto 10g        ! actual speed 10g    lag 1    exit

Access Switch Config

interface lag 1    description Uplink-Lag    no shutdown    no routing    vlan trunk native 930    vlan trunk allowed all    dhcpv4-snooping trust    lacp mode active    lacp rate fast    exitinterface 1/1/27    no shutdown    lag 1    exitinterface 1/1/28    no shutdown    lag 1    exit

Central, MultiEdit and LACP

• If you are managing these switches with Central, it is best to use MultiEdit to make these changes.
• Using the Central GUI may be challenging because you can't modify LAG member speed individually.
• You can use the CLI too, but note that after release 2.5.9, Central will overwrite changes made in support mode, so you will have to complete the whole task in less time that it takes Central to identify the changes and change them back.
• It is also important to have a loop avoidance mechanism in place. I have MSTP (basic settings as provided by the Central GUI).
  Remember that speeds cannot be mixed in a LAG - all members must be the same speed, so you cannot add a 25Gb member to a 10Gb LAG.

Upgrade from 10Gb to 25Gb

1. On agg switch, edit config for first port (1/1/27): shutdown; speed auto 25g
2. On access switch, swap in 25Gb transceiver first port (1/1/27)
   At this stage, the LAG will be active on one link only at 10Gb still
   
   
    
3. On agg switch, edit config to re-enable first port (1/1/27): no shutdown
   & edit config for second port (1/1/28): shutdown; speed auto 25g; remove from lag
   There will be some disruption here as the LAG changes from 10 to 25Gb; I usually see about 18 x 1s pings dropped.
   LAG is now up with single 25Gb member
4. On access switch, swap in 25Gb transceiver to second port (1/1/28)
5. On agg switch, edit config for second port (1/1/28): no shutdown; lag 1
   Now there is a LAG with 2 x 25Gb members.
   
   
   
    

Next step is 25 to 50Gb

The process is essentially the same again.

1. On agg switch, edit config for first port (1/1/27): shutdown; remove speed setting (default is 50Gb)
2. On access switch, swap in 50Gb transceiver first port (1/1/27)
3. On agg switch, edit config to re-enable first port (1/1/27): no shutdown
   & edit config for second port (1/1/28): shutdown; remove speed; remove from lag
   There will be some disruption here as the LAG changes from 25 to 50Gb; I usually see about 18 x 1s pings dropped.
   LAG is now up with single 50Gb member
4. On access switch, swap in 50Gb transceiver to second port (1/1/28)
5. On agg switch, edit config for second port (1/1/28): no shutdown; lag 1
   Now there is a LAG with 2 x 50Gb members.
   
   
   
    

Q&A

Q: What speeds does the tri-speed R0M48A transceiver support?
A: 10, 25 or 50Gb

Q: Will the tri-speed R0M48A run in any port?
A: It will run only in SFP56 ports. These are found in the 6300, 6400, 8360 series of CX switches. IRIS can help you configure the correct transceivers for  switches, along with the Transceiver Guide.
The output below is from a CX 6200 switch - it only has 10Gb SFP+ ports (not SFP56 like the 6300), and the 50Gb transceiver is specifically flagged as incompatible.

6200F-12# sh int 1/1/15 transceiver------------------------------------------------------------------------------Port           Type             Product          Serial           Part                                Number           Number           Number------------------------------------------------------------------------------1/1/15         50G-SR           R0M48A           MYxxxxxxxx       1990-48036200F-12# sh int 1/1/15 transceiver detailTransceiver in 1/1/15 Interface Name      : 1/1/15 Type                : 50G-SR / 50G SFP56 SR Connector Type      : LC Transceiver Status  : An HPE pluggable module that is incompatible with this interface Wavelength          : 850nm Transfer Distance   : 0.00km (SMF), 0m (OM1), 0m (OM2), 70m (OM3) Diagnostic Support  : None Product Number      : R0M48A Serial Number       : MYxxxxxxxx Part Number         : 1990-4803

Q: Is the tri-speed R0M48A auto-sensing?
A: No, it defaults to 50Gb, so you must specify 10 or 25Gb.

References

https://asp.arubanetworks.com/downloads;search=transceiver;sort=RELEASEDATE_DESC;fileTypes=DOCUMENT;products=Aruba%20Switches
AOS-Switch and AOS-CX Transceiver Guide

https://community.arubanetworks.com/viewdocument/aos-cx-1012-software-release-ente
AOS-CX 10.12 Training Materials

------------------------------
Richard Litchfield
Airheads MVP 2020, 2021, 2022
------------------------------

Hi There,

just found this interesting info.

Does it mean, with CX 10.12+ and R0M48A i could connect server using 50G? 

BR
Marcus

DACs are still supported, and make most sense for stacking within a rack or cabinet.

The 50Gb transceivers are useful for high-speed uplinks, but you could also use them for stacking: this could be useful when the switches are separated by a distance longer than a DAC supports.

From the Datasheet: DS_6300Series.pdf,:

• (note 1). 50G capability is for use with 50G DACs for both interconnect and VSF stacking

Is this not the case anymore ?

------------------------------
Steinar

Original Message:
Sent: Sep 30, 2023 10:49 AM
From: Richard Litchfield
Subject: Howto: 50Gb tri-speed transceivers

Howto: 50Gb tri-speed transceivers

Overview

HPE Aruba Networking recently released a major new firmware upgrade for CX switches with CX 10.12. One of the interesting new features is that the standard 50Gb multimode transceiver has been enabled with tri-speed mode. That's right, if you already have a R0M48A 50Gb transceiver, when you use it in switch with CX 10.12, you can run at 10, 25 or 50Gb speeds!

I will show how to do an upgrade from 10 to 25 to 50Gb with minimal downtime in this post. 

Scenario

This could be useful in scenarios such as:

• You upgrade core/aggregation switches first (eg with the CX 8360, CX 6400 models with 50Gb ports) but still need to connect to the 10Gb downstream access switches: put in 50Gb optics and run them at 10Gb until  you can upgrade the access switches
• Conversely, the access switches have been replaced with CX6300, and you want to run 25 or 50Gb uplinks, but the upstream core/agg devices only have 10 or 25Gb ports still: include 50Gb optics in the 6300 access switches and run them at the lower speed until  you can upgrade the core/agg switches

Example Step Upgrade Process

Environment

• 2 x 6300 24 port switches
• The upper switch is 6300-aggregation
• The lower switch is 6300-access
• Both switches have a pair of SFP56 ports configured as an LACP LAG (1/1/27 & 1/1/28)

In the starting configuration, the aggregation switch has an LACP LAG group running over a pair of 50Gb tri-speed transceivers configured to run at 10Gb, connected to the access switch with a pair of 10Gb transceivers.

Aggregation Switch Config

interface lag 1    description Downstream Lag    no shutdown    no routing    vlan trunk native 930    vlan trunk allowed all    lacp mode active    lacp fallback-static    lacp rate fast    exitinterface 1/1/27    no shutdown    speed auto 10g        ! actual speed 10g    lag 1    exitinterface 1/1/28    no shutdown    speed auto 10g        ! actual speed 10g    lag 1    exit

Access Switch Config

interface lag 1    description Uplink-Lag    no shutdown    no routing    vlan trunk native 930    vlan trunk allowed all    dhcpv4-snooping trust    lacp mode active    lacp rate fast    exitinterface 1/1/27    no shutdown    lag 1    exitinterface 1/1/28    no shutdown    lag 1    exit

Central, MultiEdit and LACP

• If you are managing these switches with Central, it is best to use MultiEdit to make these changes.
• Using the Central GUI may be challenging because you can't modify LAG member speed individually.
• You can use the CLI too, but note that after release 2.5.9, Central will overwrite changes made in support mode, so you will have to complete the whole task in less time that it takes Central to identify the changes and change them back.
• It is also important to have a loop avoidance mechanism in place. I have MSTP (basic settings as provided by the Central GUI).
  Remember that speeds cannot be mixed in a LAG - all members must be the same speed, so you cannot add a 25Gb member to a 10Gb LAG.

Upgrade from 10Gb to 25Gb

1. On agg switch, edit config for first port (1/1/27): shutdown; speed auto 25g
2. On access switch, swap in 25Gb transceiver first port (1/1/27)
   At this stage, the LAG will be active on one link only at 10Gb still
   
   
    
3. On agg switch, edit config to re-enable first port (1/1/27): no shutdown
   & edit config for second port (1/1/28): shutdown; speed auto 25g; remove from lag
   There will be some disruption here as the LAG changes from 10 to 25Gb; I usually see about 18 x 1s pings dropped.
   LAG is now up with single 25Gb member
4. On access switch, swap in 25Gb transceiver to second port (1/1/28)
5. On agg switch, edit config for second port (1/1/28): no shutdown; lag 1
   Now there is a LAG with 2 x 25Gb members.
   
   
   
    

Next step is 25 to 50Gb

The process is essentially the same again.

1. On agg switch, edit config for first port (1/1/27): shutdown; remove speed setting (default is 50Gb)
2. On access switch, swap in 50Gb transceiver first port (1/1/27)
3. On agg switch, edit config to re-enable first port (1/1/27): no shutdown
   & edit config for second port (1/1/28): shutdown; remove speed; remove from lag
   There will be some disruption here as the LAG changes from 25 to 50Gb; I usually see about 18 x 1s pings dropped.
   LAG is now up with single 50Gb member
4. On access switch, swap in 50Gb transceiver to second port (1/1/28)
5. On agg switch, edit config for second port (1/1/28): no shutdown; lag 1
   Now there is a LAG with 2 x 50Gb members.
   
   
   
    

Q&A

Q: What speeds does the tri-speed R0M48A transceiver support?
A: 10, 25 or 50Gb

Q: Will the tri-speed R0M48A run in any port?
A: It will run only in SFP56 ports. These are found in the 6300, 6400, 8360 series of CX switches. IRIS can help you configure the correct transceivers for  switches, along with the Transceiver Guide.
The output below is from a CX 6200 switch - it only has 10Gb SFP+ ports (not SFP56 like the 6300), and the 50Gb transceiver is specifically flagged as incompatible.

6200F-12# sh int 1/1/15 transceiver------------------------------------------------------------------------------Port           Type             Product          Serial           Part                                Number           Number           Number------------------------------------------------------------------------------1/1/15         50G-SR           R0M48A           MYxxxxxxxx       1990-48036200F-12# sh int 1/1/15 transceiver detailTransceiver in 1/1/15 Interface Name      : 1/1/15 Type                : 50G-SR / 50G SFP56 SR Connector Type      : LC Transceiver Status  : An HPE pluggable module that is incompatible with this interface Wavelength          : 850nm Transfer Distance   : 0.00km (SMF), 0m (OM1), 0m (OM2), 70m (OM3) Diagnostic Support  : None Product Number      : R0M48A Serial Number       : MYxxxxxxxx Part Number         : 1990-4803

Q: Is the tri-speed R0M48A auto-sensing?
A: No, it defaults to 50Gb, so you must specify 10 or 25Gb.

References

https://asp.arubanetworks.com/downloads;search=transceiver;sort=RELEASEDATE_DESC;fileTypes=DOCUMENT;products=Aruba%20Switches
AOS-Switch and AOS-CX Transceiver Guide

https://community.arubanetworks.com/viewdocument/aos-cx-1012-software-release-ente
AOS-CX 10.12 Training Materials

------------------------------
Richard Litchfield
Airheads MVP 2020, 2021, 2022
------------------------------

If the server has a 50Gb SFP56 port, you would be able to use a 50Gb optic (and maybe DAC) to connect that to a CX switch.

------------------------------
Richard Litchfield
Airheads MVP 2020, 2021, 2022

Original Message:
Sent: Nov 17, 2023 02:08 AM
From: snoopy78
Subject: Howto: 50Gb tri-speed transceivers

Hi There,

just found this interesting info.

Does it mean, with CX 10.12+ and R0M48A i could connect server using 50G? 

BR
Marcus

Original Message:
Sent: Oct 03, 2023 08:30 AM
From: Richard Litchfield
Subject: Howto: 50Gb tri-speed transceivers

DACs are still supported, and make most sense for stacking within a rack or cabinet.

The 50Gb transceivers are useful for high-speed uplinks, but you could also use them for stacking: this could be useful when the switches are separated by a distance longer than a DAC supports.

------------------------------
Richard Litchfield
Airheads MVP 2020, 2021, 2022

Original Message:
Sent: Oct 03, 2023 04:00 AM
From: Steinar Grande
Subject: Howto: 50Gb tri-speed transceivers

From the Datasheet: DS_6300Series.pdf,:

• (note 1). 50G capability is for use with 50G DACs for both interconnect and VSF stacking

Is this not the case anymore ?

------------------------------
Steinar

Original Message:
Sent: Sep 30, 2023 10:49 AM
From: Richard Litchfield
Subject: Howto: 50Gb tri-speed transceivers

Howto: 50Gb tri-speed transceivers

Overview

HPE Aruba Networking recently released a major new firmware upgrade for CX switches with CX 10.12. One of the interesting new features is that the standard 50Gb multimode transceiver has been enabled with tri-speed mode. That's right, if you already have a R0M48A 50Gb transceiver, when you use it in switch with CX 10.12, you can run at 10, 25 or 50Gb speeds!

I will show how to do an upgrade from 10 to 25 to 50Gb with minimal downtime in this post. 

Scenario

This could be useful in scenarios such as:

• You upgrade core/aggregation switches first (eg with the CX 8360, CX 6400 models with 50Gb ports) but still need to connect to the 10Gb downstream access switches: put in 50Gb optics and run them at 10Gb until  you can upgrade the access switches
• Conversely, the access switches have been replaced with CX6300, and you want to run 25 or 50Gb uplinks, but the upstream core/agg devices only have 10 or 25Gb ports still: include 50Gb optics in the 6300 access switches and run them at the lower speed until  you can upgrade the core/agg switches

Example Step Upgrade Process

Environment

• 2 x 6300 24 port switches
• The upper switch is 6300-aggregation
• The lower switch is 6300-access
• Both switches have a pair of SFP56 ports configured as an LACP LAG (1/1/27 & 1/1/28)

In the starting configuration, the aggregation switch has an LACP LAG group running over a pair of 50Gb tri-speed transceivers configured to run at 10Gb, connected to the access switch with a pair of 10Gb transceivers.

Aggregation Switch Config

interface lag 1    description Downstream Lag    no shutdown    no routing    vlan trunk native 930    vlan trunk allowed all    lacp mode active    lacp fallback-static    lacp rate fast    exitinterface 1/1/27    no shutdown    speed auto 10g        ! actual speed 10g    lag 1    exitinterface 1/1/28    no shutdown    speed auto 10g        ! actual speed 10g    lag 1    exit

Access Switch Config

interface lag 1    description Uplink-Lag    no shutdown    no routing    vlan trunk native 930    vlan trunk allowed all    dhcpv4-snooping trust    lacp mode active    lacp rate fast    exitinterface 1/1/27    no shutdown    lag 1    exitinterface 1/1/28    no shutdown    lag 1    exit

Central, MultiEdit and LACP

• If you are managing these switches with Central, it is best to use MultiEdit to make these changes.
• Using the Central GUI may be challenging because you can't modify LAG member speed individually.
• You can use the CLI too, but note that after release 2.5.9, Central will overwrite changes made in support mode, so you will have to complete the whole task in less time that it takes Central to identify the changes and change them back.
• It is also important to have a loop avoidance mechanism in place. I have MSTP (basic settings as provided by the Central GUI).
  Remember that speeds cannot be mixed in a LAG - all members must be the same speed, so you cannot add a 25Gb member to a 10Gb LAG.

Upgrade from 10Gb to 25Gb

1. On agg switch, edit config for first port (1/1/27): shutdown; speed auto 25g
2. On access switch, swap in 25Gb transceiver first port (1/1/27)
   At this stage, the LAG will be active on one link only at 10Gb still
   
   
    
3. On agg switch, edit config to re-enable first port (1/1/27): no shutdown
   & edit config for second port (1/1/28): shutdown; speed auto 25g; remove from lag
   There will be some disruption here as the LAG changes from 10 to 25Gb; I usually see about 18 x 1s pings dropped.
   LAG is now up with single 25Gb member
4. On access switch, swap in 25Gb transceiver to second port (1/1/28)
5. On agg switch, edit config for second port (1/1/28): no shutdown; lag 1
   Now there is a LAG with 2 x 25Gb members.
   
   
   
    

Next step is 25 to 50Gb

The process is essentially the same again.

1. On agg switch, edit config for first port (1/1/27): shutdown; remove speed setting (default is 50Gb)
2. On access switch, swap in 50Gb transceiver first port (1/1/27)
3. On agg switch, edit config to re-enable first port (1/1/27): no shutdown
   & edit config for second port (1/1/28): shutdown; remove speed; remove from lag
   There will be some disruption here as the LAG changes from 25 to 50Gb; I usually see about 18 x 1s pings dropped.
   LAG is now up with single 50Gb member
4. On access switch, swap in 50Gb transceiver to second port (1/1/28)
5. On agg switch, edit config for second port (1/1/28): no shutdown; lag 1
   Now there is a LAG with 2 x 50Gb members.
   
   
   
    

Q&A

Q: What speeds does the tri-speed R0M48A transceiver support?
A: 10, 25 or 50Gb

Q: Will the tri-speed R0M48A run in any port?
A: It will run only in SFP56 ports. These are found in the 6300, 6400, 8360 series of CX switches. IRIS can help you configure the correct transceivers for  switches, along with the Transceiver Guide.
The output below is from a CX 6200 switch - it only has 10Gb SFP+ ports (not SFP56 like the 6300), and the 50Gb transceiver is specifically flagged as incompatible.

6200F-12# sh int 1/1/15 transceiver------------------------------------------------------------------------------Port           Type             Product          Serial           Part                                Number           Number           Number------------------------------------------------------------------------------1/1/15         50G-SR           R0M48A           MYxxxxxxxx       1990-48036200F-12# sh int 1/1/15 transceiver detailTransceiver in 1/1/15 Interface Name      : 1/1/15 Type                : 50G-SR / 50G SFP56 SR Connector Type      : LC Transceiver Status  : An HPE pluggable module that is incompatible with this interface Wavelength          : 850nm Transfer Distance   : 0.00km (SMF), 0m (OM1), 0m (OM2), 70m (OM3) Diagnostic Support  : None Product Number      : R0M48A Serial Number       : MYxxxxxxxx Part Number         : 1990-4803

Q: Is the tri-speed R0M48A auto-sensing?
A: No, it defaults to 50Gb, so you must specify 10 or 25Gb.

References

https://asp.arubanetworks.com/downloads;search=transceiver;sort=RELEASEDATE_DESC;fileTypes=DOCUMENT;products=Aruba%20Switches
AOS-Switch and AOS-CX Transceiver Guide

https://community.arubanetworks.com/viewdocument/aos-cx-1012-software-release-ente
AOS-CX 10.12 Training Materials

------------------------------
Richard Litchfield
Airheads MVP 2020, 2021, 2022
------------------------------