while there, here is another one (just below that one) :) which I learned the very hard way, after 2 years in production (when clients started complaining on random traffic drop) : http://docs.cloudstack.apache.org/en/latest/networking/vxlan.html#important-note-on-max-number-of-multicast-groups-and-thus-vxlan-intefaces
Very sneaky and ugly: Ubuntu kernel 3.16 = random traffic drops, but all vxlan interfaces are UP etc..., Ubuntu kernel 4.x vxlan interface would NOT come up AT ALL, so a hard drop of packets, and there is where we saw the issue... Cheers On 21 December 2017 at 15:13, Nux! <n...@li.nux.ro> wrote: > Thanks Andrija, well done, I have indeed read your document. > Using MTU 9000 solved my problem. :) > > Lucian > > -- > Sent from the Delta quadrant using Borg technology! > > Nux! > www.nux.ro > > ----- Original Message ----- > > From: "Andrija Panic" <andrija.pa...@gmail.com> > > To: "dev" <dev@cloudstack.apache.org> > > Cc: "users" <us...@cloudstack.apache.org> > > Sent: Thursday, 21 December, 2017 14:09:43 > > Subject: Re: Circumventing VXLAN MTU issues > > > Hi Nux, > > > > there is one rare contributions from my side :D to the ACS > (documentation, > > 2.5 years ago) - check it here: > > http://docs.cloudstack.apache.org/en/latest/networking/ > vxlan.html#important-note-on-mtu-size > > > > We are using it extensively, feel free to ask anything if needed. > > > > Cheers > > > > On 20 November 2017 at 19:38, Nux! <n...@li.nux.ro> wrote: > > > >> Yeah, I changed the MTU to 9000 on the Guest network interface and > >> connectivity is now fine out of the box. > >> Hopefully I won't need to set jumbo frames in the VMs any time soon. :-) > >> > >> Thanks for the tips. > >> > >> Lucian > >> > >> -- > >> Sent from the Delta quadrant using Borg technology! > >> > >> Nux! > >> www.nux.ro > >> > >> ----- Original Message ----- > >> > From: "Simon Weller" <swel...@ena.com.INVALID> > >> > To: "users" <us...@cloudstack.apache.org> > >> > Cc: "dev" <dev@cloudstack.apache.org> > >> > Sent: Monday, 20 November, 2017 17:36:31 > >> > Subject: Re: Circumventing VXLAN MTU issues > >> > >> > Change your host interface MTU to something a lot higher. > >> > > >> > > >> > ________________________________ > >> > From: Nux! <n...@li.nux.ro> > >> > Sent: Monday, November 20, 2017 10:51 AM > >> > To: users > >> > Cc: dev > >> > Subject: Re: Circumventing VXLAN MTU issues > >> > > >> > Hi, > >> > > >> > I probably can use jumbo frames, but for now my lab is restricted to a > >> single > >> > machine. > >> > Anything I can do in this situation? > >> > > >> > -- > >> > Sent from the Delta quadrant using Borg technology! > >> > > >> > Nux! > >> > www.nux.ro > >> > > >> > ----- Original Message ----- > >> >> From: "Simon Weller" <swel...@ena.com.INVALID> > >> >> To: "dev" <dev@cloudstack.apache.org>, "users" < > >> us...@cloudstack.apache.org> > >> >> Sent: Monday, 20 November, 2017 16:38:33 > >> >> Subject: Re: Circumventing VXLAN MTU issues > >> > > >> >> Lucian, > >> >> > >> >> Can you run jumbos on your switches? > >> >> > >> >> - Si > >> >> > >> >> > >> >> ________________________________ > >> >> From: Nux! <n...@li.nux.ro> > >> >> Sent: Monday, November 20, 2017 10:08 AM > >> >> To: dev > >> >> Cc: users > >> >> Subject: Circumventing VXLAN MTU issues > >> >> > >> >> Hello, > >> >> > >> >> I am playing around with the native VXLAN implementation and I have > of > >> course > >> >> hit the situation where MTU on the host gets chomped by 50 bytes and > >> traffic > >> >> crawls to a stop in the VMs. > >> >> How are you people circumventing this? The easiest, but kind of > >> inconvenient for > >> >> customers would be to set MTU 1450 inside the VM, though it could be > >> baked into > >> >> the templates or via cloud-init. > >> >> > >> >> Is the OpenVSwitch implementation (of VXLAN) suffer from the same > >> problem, I > >> >> understand ovs can dynamically adjust MTUs to compensate (?), but at > >> the same > >> >> time this VXLAN implementation suffers from some limitations > (multicast > >> etc). > >> >> > >> >> Lucian > >> >> > >> >> > >> >> -- > >> >> Sent from the Delta quadrant using Borg technology! > >> >> > >> >> Nux! > >> > > www.nux.ro > >> > > > > > > > > -- > > > > Andrija Panić > -- Andrija Panić
