Fix for mtu issues with kernelvethpair #452
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This *probably* fixes: networkservicemesh/sdk#1148 The underlying issue was that the end of the vethpair to which VPP was attaching with afpacket was not getting its MTU set correctly. As a result, if an oversized packet was sent over it, it would be fragmented by the kernel to a size that matches the mtu on the end of the veth pair that was in the NSC network namespace. The resulting packet would *still* be to large for the MTU of the end of the vethpair attached to the VPP instance, and would be dropped there. The second fragment, being smaller, would be smaller than the MTU of the end of the vethpair to which VPP was attached with af-packet, and so get through. Signed-off-by: Ed Warnicke <hagbard@gmail.com>
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…k-vpp@main PR link: networkservicemesh/sdk-vpp#452 Commit: 7958db6 Author: Ed Warnicke Date: 2021-11-22 09:09:20 -0600 Message: - Fix for mtu issues with kernelvethpair (#452) This *probably* fixes: networkservicemesh/sdk#1148 The underlying issue was that the end of the vethpair to which VPP was attaching with afpacket was not getting its MTU set correctly. As a result, if an oversized packet was sent over it, it would be fragmented by the kernel to a size that matches the mtu on the end of the veth pair that was in the NSC network namespace. The resulting packet would *still* be to large for the MTU of the end of the vethpair attached to the VPP instance, and would be dropped there. The second fragment, being smaller, would be smaller than the MTU of the end of the vethpair to which VPP was attached with af-packet, and so get through. Signed-off-by: NSMBot <nsmbot@networkservicmesh.io>
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…k-vpp@main PR link: networkservicemesh/sdk-vpp#452 Commit: 7958db6 Author: Ed Warnicke Date: 2021-11-22 09:09:20 -0600 Message: - Fix for mtu issues with kernelvethpair (#452) This *probably* fixes: networkservicemesh/sdk#1148 The underlying issue was that the end of the vethpair to which VPP was attaching with afpacket was not getting its MTU set correctly. As a result, if an oversized packet was sent over it, it would be fragmented by the kernel to a size that matches the mtu on the end of the veth pair that was in the NSC network namespace. The resulting packet would *still* be to large for the MTU of the end of the vethpair attached to the VPP instance, and would be dropped there. The second fragment, being smaller, would be smaller than the MTU of the end of the vethpair to which VPP was attached with af-packet, and so get through. Signed-off-by: NSMBot <nsmbot@networkservicmesh.io>
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…k-vpp@main PR link: networkservicemesh/sdk-vpp#452 Commit: 7958db6 Author: Ed Warnicke Date: 2021-11-22 09:09:20 -0600 Message: - Fix for mtu issues with kernelvethpair (#452) This *probably* fixes: networkservicemesh/sdk#1148 The underlying issue was that the end of the vethpair to which VPP was attaching with afpacket was not getting its MTU set correctly. As a result, if an oversized packet was sent over it, it would be fragmented by the kernel to a size that matches the mtu on the end of the veth pair that was in the NSC network namespace. The resulting packet would *still* be to large for the MTU of the end of the vethpair attached to the VPP instance, and would be dropped there. The second fragment, being smaller, would be smaller than the MTU of the end of the vethpair to which VPP was attached with af-packet, and so get through. Signed-off-by: NSMBot <nsmbot@networkservicmesh.io>
nsmbot
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…k-vpp@main PR link: networkservicemesh/sdk-vpp#452 Commit: 7958db6 Author: Ed Warnicke Date: 2021-11-22 09:09:20 -0600 Message: - Fix for mtu issues with kernelvethpair (#452) This *probably* fixes: networkservicemesh/sdk#1148 The underlying issue was that the end of the vethpair to which VPP was attaching with afpacket was not getting its MTU set correctly. As a result, if an oversized packet was sent over it, it would be fragmented by the kernel to a size that matches the mtu on the end of the veth pair that was in the NSC network namespace. The resulting packet would *still* be to large for the MTU of the end of the vethpair attached to the VPP instance, and would be dropped there. The second fragment, being smaller, would be smaller than the MTU of the end of the vethpair to which VPP was attached with af-packet, and so get through. Signed-off-by: NSMBot <nsmbot@networkservicmesh.io>
This was referenced Nov 22, 2021
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This probably fixes:
networkservicemesh/sdk#1148
The underlying issue was that the end of the vethpair to which
VPP was attaching with afpacket was not getting its MTU set correctly.
As a result, if an oversized packet was sent over it, it would be fragmented
by the kernel to a size that matches the mtu on the end of the veth pair
that was in the NSC network namespace.
The resulting packet would still be to large for the MTU of the end of the
vethpair attached to the VPP instance, and would be dropped there.
The second fragment, being smaller, would be smaller than the MTU of the
end of the vethpair to which VPP was attached with af-packet, and so get
through.
Signed-off-by: Ed Warnicke hagbard@gmail.com