Re: [PATCH net-next v7 0/4] net: Introduce protodown flag.
From: anurad...@cumulusnetworks.com Date: Tue, 14 Jul 2015 13:43:18 -0700 User space daemons can detect errors in the network that need to be notified to the switch device drivers. Drivers can react to this error state by doing a phy-down on the switch-port which would result in a carrier-off locally and on the directly connected switch. Doing that would prevent loops and black-holes in the network. Series applied, thanks. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next v7 0/4] net: Introduce protodown flag.
On Wed, Jul 15, 2015 at 8:53 AM, Anuradha Karuppiah anurad...@cumulusnetworks.com wrote: On Tue, Jul 14, 2015 at 10:08 PM, Scott Feldman sfel...@gmail.com wrote: On Tue, Jul 14, 2015 at 1:43 PM, anurad...@cumulusnetworks.com wrote: From: Anuradha Karuppiah anurad...@cumulusnetworks.com User space daemons can detect errors in the network that need to be notified to the switch device drivers. Drivers can react to this error state by doing a phy-down on the switch-port which would result in a carrier-off locally and on the directly connected switch. Doing that would prevent loops and black-holes in the network. Hi Anuradha, Since this is a switch-thingy, can you move this to switchdev port attribute rather than adding another ndo op? I know you started this patch set before switchdev port attrs, but I think it's worthwhile moving it to switchdev since clearly the use-case is switch device drivers. Let me know if you need help converting over to switchdev port attr. Also, is the sysfs interface necessary? The netlink/iproute2 interface seems sufficient. -scott Yes, for the current use case (MLAG) it would be better to isolate the changes to switchdev. Also if we go with the switchdev option are you thinking about dropping the netdev-proto_down bool attribute altogether and only keeping that info in the switch drivers that support the op? Yes. You are right, the sysfs is not necessary. I can make it RO and just use it for displaying or drop it all together. What would you recommend? Drop it if it's not needed/used. On the iproute2 part, do we expect users to manually toggle this flag from the cmdline? Seems kind of weird to walk up to a box and say ip link set dev DEV protodown on. Isn't this more intended for external agents (i.e. MLAG) to toggle? I guess if there is a netlink attr for the flag, there should be a user-interface. But it seems like it'll be a source of confusion for 99.999% of the users out there that wonder what this knob does. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next v7 0/4] net: Introduce protodown flag.
On Wed, Jul 15, 2015 at 11:29 AM, Scott Feldman sfel...@gmail.com wrote: On Wed, Jul 15, 2015 at 8:53 AM, Anuradha Karuppiah anurad...@cumulusnetworks.com wrote: On Tue, Jul 14, 2015 at 10:08 PM, Scott Feldman sfel...@gmail.com wrote: On Tue, Jul 14, 2015 at 1:43 PM, anurad...@cumulusnetworks.com wrote: From: Anuradha Karuppiah anurad...@cumulusnetworks.com User space daemons can detect errors in the network that need to be notified to the switch device drivers. Drivers can react to this error state by doing a phy-down on the switch-port which would result in a carrier-off locally and on the directly connected switch. Doing that would prevent loops and black-holes in the network. Hi Anuradha, Since this is a switch-thingy, can you move this to switchdev port attribute rather than adding another ndo op? I know you started this patch set before switchdev port attrs, but I think it's worthwhile moving it to switchdev since clearly the use-case is switch device drivers. Let me know if you need help converting over to switchdev port attr. Also, is the sysfs interface necessary? The netlink/iproute2 interface seems sufficient. -scott Yes, for the current use case (MLAG) it would be better to isolate the changes to switchdev. Also if we go with the switchdev option are you thinking about dropping the netdev-proto_down bool attribute altogether and only keeping that info in the switch drivers that support the op? Yes. You are right, the sysfs is not necessary. I can make it RO and just use it for displaying or drop it all together. What would you recommend? Drop it if it's not needed/used. On the iproute2 part, do we expect users to manually toggle this flag from the cmdline? Seems kind of weird to walk up to a box and say ip link set dev DEV protodown on. Isn't this more intended for external agents (i.e. MLAG) to toggle? I guess if there is a netlink attr for the flag, there should be a user-interface. But it seems like it'll be a source of confusion for 99.999% of the users out there that wonder what this knob does. The MLAG app currently does use the iproute2 interface for toggling protodown. So I may not be able to drop the iproute2 config option easily. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next v7 0/4] net: Introduce protodown flag.
On Wed, Jul 15, 2015 at 11:36 AM, Anuradha Karuppiah anurad...@cumulusnetworks.com wrote: On Wed, Jul 15, 2015 at 11:29 AM, Scott Feldman sfel...@gmail.com wrote: On Wed, Jul 15, 2015 at 8:53 AM, Anuradha Karuppiah anurad...@cumulusnetworks.com wrote: On Tue, Jul 14, 2015 at 10:08 PM, Scott Feldman sfel...@gmail.com wrote: On Tue, Jul 14, 2015 at 1:43 PM, anurad...@cumulusnetworks.com wrote: From: Anuradha Karuppiah anurad...@cumulusnetworks.com User space daemons can detect errors in the network that need to be notified to the switch device drivers. Drivers can react to this error state by doing a phy-down on the switch-port which would result in a carrier-off locally and on the directly connected switch. Doing that would prevent loops and black-holes in the network. Hi Anuradha, Since this is a switch-thingy, can you move this to switchdev port attribute rather than adding another ndo op? I know you started this patch set before switchdev port attrs, but I think it's worthwhile moving it to switchdev since clearly the use-case is switch device drivers. Let me know if you need help converting over to switchdev port attr. Also, is the sysfs interface necessary? The netlink/iproute2 interface seems sufficient. -scott Yes, for the current use case (MLAG) it would be better to isolate the changes to switchdev. Also if we go with the switchdev option are you thinking about dropping the netdev-proto_down bool attribute altogether and only keeping that info in the switch drivers that support the op? Yes. You are right, the sysfs is not necessary. I can make it RO and just use it for displaying or drop it all together. What would you recommend? Drop it if it's not needed/used. On the iproute2 part, do we expect users to manually toggle this flag from the cmdline? Seems kind of weird to walk up to a box and say ip link set dev DEV protodown on. Isn't this more intended for external agents (i.e. MLAG) to toggle? I guess if there is a netlink attr for the flag, there should be a user-interface. But it seems like it'll be a source of confusion for 99.999% of the users out there that wonder what this knob does. The MLAG app currently does use the iproute2 interface for toggling protodown. So I may not be able to drop the iproute2 config option easily. It can send netlink msg directly as easy as doing exec ip link set ..., I assume. Forgive me if I've asked this before: where is this MLAG app? -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next v7 0/4] net: Introduce protodown flag.
On Wed, Jul 15, 2015 at 11:46 AM, Scott Feldman sfel...@gmail.com wrote: On Wed, Jul 15, 2015 at 11:36 AM, Anuradha Karuppiah anurad...@cumulusnetworks.com wrote: On Wed, Jul 15, 2015 at 11:29 AM, Scott Feldman sfel...@gmail.com wrote: On Wed, Jul 15, 2015 at 8:53 AM, Anuradha Karuppiah anurad...@cumulusnetworks.com wrote: On Tue, Jul 14, 2015 at 10:08 PM, Scott Feldman sfel...@gmail.com wrote: On Tue, Jul 14, 2015 at 1:43 PM, anurad...@cumulusnetworks.com wrote: From: Anuradha Karuppiah anurad...@cumulusnetworks.com User space daemons can detect errors in the network that need to be notified to the switch device drivers. Drivers can react to this error state by doing a phy-down on the switch-port which would result in a carrier-off locally and on the directly connected switch. Doing that would prevent loops and black-holes in the network. Hi Anuradha, Since this is a switch-thingy, can you move this to switchdev port attribute rather than adding another ndo op? I know you started this patch set before switchdev port attrs, but I think it's worthwhile moving it to switchdev since clearly the use-case is switch device drivers. Let me know if you need help converting over to switchdev port attr. Also, is the sysfs interface necessary? The netlink/iproute2 interface seems sufficient. -scott Yes, for the current use case (MLAG) it would be better to isolate the changes to switchdev. Also if we go with the switchdev option are you thinking about dropping the netdev-proto_down bool attribute altogether and only keeping that info in the switch drivers that support the op? Yes. You are right, the sysfs is not necessary. I can make it RO and just use it for displaying or drop it all together. What would you recommend? Drop it if it's not needed/used. On the iproute2 part, do we expect users to manually toggle this flag from the cmdline? Seems kind of weird to walk up to a box and say ip link set dev DEV protodown on. Isn't this more intended for external agents (i.e. MLAG) to toggle? I guess if there is a netlink attr for the flag, there should be a user-interface. But it seems like it'll be a source of confusion for 99.999% of the users out there that wonder what this knob does. The MLAG app currently does use the iproute2 interface for toggling protodown. So I may not be able to drop the iproute2 config option easily. It can send netlink msg directly as easy as doing exec ip link set ..., I assume. Forgive me if I've asked this before: where is this MLAG app? We are in the process of making the app ready for open-sourcing and upstreaming this patch set was part of that. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next v7 0/4] net: Introduce protodown flag.
On Wed, Jul 15, 2015 at 11:29:55AM -0700, Scott Feldman wrote: [...] On the iproute2 part, do we expect users to manually toggle this flag from the cmdline? Seems kind of weird to walk up to a box and say ip link set dev DEV protodown on. Isn't this more intended for external agents (i.e. MLAG) to toggle? I guess if there is a netlink attr for the flag, there should be a user-interface. But it seems like it'll be a source of confusion for 99.999% of the users out there that wonder what this knob does. I would want to have it in iproute2 the event that I killed an app that set this flag for me. This would allow me to clear the bit and use the interface as I pleased. I would not want to have to reboot just to use my device again. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next v7 0/4] net: Introduce protodown flag.
On Wed, Jul 15, 2015 at 9:24 AM, Andy Gospodarek go...@cumulusnetworks.com wrote: On Tue, Jul 14, 2015 at 10:08:35PM -0700, Scott Feldman wrote: On Tue, Jul 14, 2015 at 1:43 PM, anurad...@cumulusnetworks.com wrote: From: Anuradha Karuppiah anurad...@cumulusnetworks.com User space daemons can detect errors in the network that need to be notified to the switch device drivers. Drivers can react to this error state by doing a phy-down on the switch-port which would result in a carrier-off locally and on the directly connected switch. Doing that would prevent loops and black-holes in the network. Hi Anuradha, Since this is a switch-thingy, can you move this to switchdev port attribute rather than adding another ndo op? I know you started this patch set before switchdev port attrs, but I think it's worthwhile moving it to switchdev since clearly the use-case is switch device drivers. Let me know if you need help converting over to switchdev port attr. If it is switchdev-only that would prevent people from using commodity hardware (classic servers + NICs) from being able to build something similar to what can be done with rocker. That's not true. There is nothing preventing a classic NIC driver from implementing some/all switchdev ops if the device can do forwarding offload or other switchy-things. This patchset is about a switch feature (MLAG was the example use-case), so let's move this under switchdev. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next v7 0/4] net: Introduce protodown flag.
On Wed, Jul 15, 2015 at 10:34:04AM -0700, Scott Feldman wrote: On Wed, Jul 15, 2015 at 9:24 AM, Andy Gospodarek go...@cumulusnetworks.com wrote: On Tue, Jul 14, 2015 at 10:08:35PM -0700, Scott Feldman wrote: On Tue, Jul 14, 2015 at 1:43 PM, anurad...@cumulusnetworks.com wrote: From: Anuradha Karuppiah anurad...@cumulusnetworks.com User space daemons can detect errors in the network that need to be notified to the switch device drivers. Drivers can react to this error state by doing a phy-down on the switch-port which would result in a carrier-off locally and on the directly connected switch. Doing that would prevent loops and black-holes in the network. Hi Anuradha, Since this is a switch-thingy, can you move this to switchdev port attribute rather than adding another ndo op? I know you started this patch set before switchdev port attrs, but I think it's worthwhile moving it to switchdev since clearly the use-case is switch device drivers. Let me know if you need help converting over to switchdev port attr. If it is switchdev-only that would prevent people from using commodity hardware (classic servers + NICs) from being able to build something similar to what can be done with rocker. That's not true. There is nothing preventing a classic NIC driver from implementing some/all switchdev ops if the device can do forwarding offload or other switchy-things. I thought the point of the switchdev ops were to provide offload-specific capabilities not just switch-specific functions. Having it in switchdev seems misplaced architecturally and seems less likely to have it accepted by NIC drivers that desire this functionality. This patchset is about a switch feature (MLAG was the example use-case), so let's move this under switchdev. As you have stated the need for it was evidenced when using a non-LACP multi-chassis bond as there was no viable way to tell a device connectad via a static bond that the traffic it received would be dropped. Generally, the use-case for the proto-down feature is to have a way to tell a connected device to stop sending traffic towards our device in a particular scenario. I'm certain there are times when an endpoint might also want to take down an interface to get an upstream device to stop sending traffic without dealing with all the baggage that comes with taking an inteface admin down. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next v7 0/4] net: Introduce protodown flag.
From: Andy Gospodarek go...@cumulusnetworks.com Date: Wed, 15 Jul 2015 12:24:35 -0400 If it is switchdev-only that would prevent people from using commodity hardware (classic servers + NICs) from being able to build something similar to what can be done with rocker. Agreed, this isn't switchdev specific at all. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next v7 0/4] net: Introduce protodown flag.
On Tue, Jul 14, 2015 at 10:08 PM, Scott Feldman sfel...@gmail.com wrote: On Tue, Jul 14, 2015 at 1:43 PM, anurad...@cumulusnetworks.com wrote: From: Anuradha Karuppiah anurad...@cumulusnetworks.com User space daemons can detect errors in the network that need to be notified to the switch device drivers. Drivers can react to this error state by doing a phy-down on the switch-port which would result in a carrier-off locally and on the directly connected switch. Doing that would prevent loops and black-holes in the network. Hi Anuradha, Since this is a switch-thingy, can you move this to switchdev port attribute rather than adding another ndo op? I know you started this patch set before switchdev port attrs, but I think it's worthwhile moving it to switchdev since clearly the use-case is switch device drivers. Let me know if you need help converting over to switchdev port attr. Also, is the sysfs interface necessary? The netlink/iproute2 interface seems sufficient. -scott Yes, for the current use case (MLAG) it would be better to isolate the changes to switchdev. Also if we go with the switchdev option are you thinking about dropping the netdev-proto_down bool attribute altogether and only keeping that info in the switch drivers that support the op? You are right, the sysfs is not necessary. I can make it RO and just use it for displaying or drop it all together. What would you recommend? Anuradha. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next v7 0/4] net: Introduce protodown flag.
On Tue, Jul 14, 2015 at 10:08:35PM -0700, Scott Feldman wrote: On Tue, Jul 14, 2015 at 1:43 PM, anurad...@cumulusnetworks.com wrote: From: Anuradha Karuppiah anurad...@cumulusnetworks.com User space daemons can detect errors in the network that need to be notified to the switch device drivers. Drivers can react to this error state by doing a phy-down on the switch-port which would result in a carrier-off locally and on the directly connected switch. Doing that would prevent loops and black-holes in the network. Hi Anuradha, Since this is a switch-thingy, can you move this to switchdev port attribute rather than adding another ndo op? I know you started this patch set before switchdev port attrs, but I think it's worthwhile moving it to switchdev since clearly the use-case is switch device drivers. Let me know if you need help converting over to switchdev port attr. If it is switchdev-only that would prevent people from using commodity hardware (classic servers + NICs) from being able to build something similar to what can be done with rocker. It is a fact that many smaller providers build forwarding devices like this, so I'd hate to limit functionality to just switchdev-based devices. My vote would be to keep this as a base netdev function as proposed. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH net-next v7 0/4] net: Introduce protodown flag.
From: Anuradha Karuppiah anurad...@cumulusnetworks.com User space daemons can detect errors in the network that need to be notified to the switch device drivers. Drivers can react to this error state by doing a phy-down on the switch-port which would result in a carrier-off locally and on the directly connected switch. Doing that would prevent loops and black-holes in the network. One such use case is the multi-chassis LAG application - 1. The MLAG application runs on peer switches (say Switch0 and Switch1) synchronizing states, forwarding entries etc. between the two switches over the peer-link (this is a link directly connecting the two switches). 2. An MLAG election process designates one of the switches as a primary (for e.g. Switch0 is primary and Switch1 is secondary). 3. The peer link plays a critical role in allowing Switch0-Switch1 to function as a single LAG partner to the downstream dual-connected servers. When the peer-link between the switches goes down we have a split-brain situation. Switch0 and Switch1 are no longer in sync and are acting independently. This can result in traffic loops and traffic black-holing in the network. 4. To prevent these problems the MLAG application on the secondary switch phy-downs the MLAG ports on detecting the peer-link down. This will be seen as a carrier down on servers that are dual-connected to Switch0 and Switch1. 5. Specifically a dual-connected server will see a carrier-down on the port connected to the MLAG secondary, Switch1, and will stop using that port for traffic TX. So traffic black holing is prevented. v6 to v7: Removed some unnecessary code in response to review comments. v5 to v6: Replaced proto_flags with a simple proto_down boolean attribute in response to Dave's comments. v4 to v5: Changed the ip link display format for protodown to match the set as recommended by Stephen. v3 to v4: I have moved protodown out of IFF_XXX and introduced a separate proto_flags field with IF_PROTOF_DOWN bit being used by apps to notify switch port errors. This is in response to Stephen's comments that adding a new IFF_XXX may break user space. I have used rocker as the sample switch driver. And to test this functionality I used the qemu-rocker patch that Scott sent out in response to the v3 posting (needed to set link up/down when phy is enabled/disabled). v1 to v2: Based on Dave's suggestion I have moved out aggregating of error bits across applications to a user space framework. This patch now simply notifies an aggregated error bit to drivers enabling them to handle the error gracefully. Anuradha Karuppiah (4): net core: Add protodown support. netlink: changes for setting and clearing protodown via netlink. rocker: Handle protodown notifications. ip link: proto_down config and display. Signed-off-by: Anuradha Karuppiah anurad...@cumulusnetworks.com Signed-off-by: Andy Gospodarek go...@cumulusnetworks.com Signed-off-by: Roopa Prabhu ro...@cumulusnetworks.com Signed-off-by: Wilson Kok w...@cumulusnetworks.com drivers/net/ethernet/rocker/rocker.c | 19 ++- include/linux/netdevice.h| 14 ++ include/uapi/linux/if_link.h |1 + net/core/dev.c | 20 net/core/net-sysfs.c | 14 ++ net/core/rtnetlink.c | 16 ++-- 6 files changed, 81 insertions(+), 3 deletions(-) -- 1.7.10.4 -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next v7 0/4] net: Introduce protodown flag.
On Tue, Jul 14, 2015 at 1:43 PM, anurad...@cumulusnetworks.com wrote: From: Anuradha Karuppiah anurad...@cumulusnetworks.com User space daemons can detect errors in the network that need to be notified to the switch device drivers. Drivers can react to this error state by doing a phy-down on the switch-port which would result in a carrier-off locally and on the directly connected switch. Doing that would prevent loops and black-holes in the network. Hi Anuradha, Since this is a switch-thingy, can you move this to switchdev port attribute rather than adding another ndo op? I know you started this patch set before switchdev port attrs, but I think it's worthwhile moving it to switchdev since clearly the use-case is switch device drivers. Let me know if you need help converting over to switchdev port attr. Also, is the sysfs interface necessary? The netlink/iproute2 interface seems sufficient. -scott -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
