Thanks Jeff and Oren for the discussion. I agree now that lat/long from CZF is the “average” location of clients, and lat/long from Ops is the location of a certain Cache Group. So it appears to be reasonable to use them as source and dest to calculate the distance.
Thanks, John On 30/03/2017, 6:55 PM, "Oren Shemesh" <[email protected]> wrote: Jeff, having read this conversation more than once, I believe there is a misunderstanding regarding the ability to provide coordinates for cache groups both in the CZF and in the TO DB. Here is what I believe is a description which may help understanding the current behaviour: The coordinates specified in the CZF for a cache group are not supposed to be the exactly same as the coordinates in the TO DB for the same cache group. This is because they do not represent the location of the caches of the group. They represent the (average) location of clients found in the subnets specified for this cache group. This, I believe, explains both the behaviour of the code (Why the coordinates from the CZF are used for the source, but the coordinates from the TO DB are used for the various candidate cache groups), and the fact that there is a 'duplication'. Is this description true ? On Wed, Mar 29, 2017 at 7:02 PM, Jeff Elsloo <[email protected]> wrote: > The cachegroup settings in the Traffic Ops GUI end up in the > `edgeLocations` section of the CRConfig. This is the source of truth > for where caches are deployed, logically or physically. We do not > provide a means to generate a CZF in Traffic Ops, so it's up to the > end user to craft one to match what is in Traffic Ops. > > There are several cases that need to be accounted for where a hit in > the CZF does match what's in `edgeLocations`, but cannot be served > there due to cache health, delivery service health, or delivery > service assignments. The other edge case is a hit where no > `edgeLocation` exists, which again, must be accounted for. Presumably > we have higher fidelity data in our CZF than we would in our > Geolocation provider and we should use it whenever possible. > > Think about this: what if you use the same CZF for two configured > CDNs, but one of the two CDNs only has caches deployed to 50% of the > cache groups defined in the CZF. Would we want to use the Geolocation > provider in the event that our source address matches a cachegroup > that does not have any assigned caches? We would ideally have as much > granularity as possible in the CZF, then use that to inform the > decision about which cachegroup should service the request instead of > falling back to a lower fidelity datasource. This is especially true > in the case of RFC 1918 addresses that might appear in one's CZF. > > Thanks, > Jeff > > > On Wed, Mar 29, 2017 at 9:12 AM, John Shen (weifensh) > <[email protected]> wrote: > > Hi Jeff, > > > > Thank you for the detail. I am wondering why there are two sets of > lat/lang, > > i.e. one in CZF, the other is in Ops GUI Cache Group setting. To > calculate > > the closest CG when matched CG in CZF is not available, the source > lat/long > > is from mathced CZF, and the dest lat/long is from Ops setting, which > doesnt > > seem to be consistent. Is there any reason why TR has this behavior? > > > > Since there are two sets of lat/long in TR, can we just use the lat/long > all > > from Ops CG settings to get the closest, and do not care about the values > > set in CZF? At least this will avoid inconsistent config for lat/long. > > > > Thanks, > > John > > > > ---Original--- > > From: "Jeff Elsloo "<[email protected]> > > Date: 2017/3/29 22:45:12 > > To: > > "[email protected]"<[email protected]. > apache.org>; > > Subject: Re: Backup Cache Group Selection > > > > Yes, it's expected behavior. What you're describing sounds like a > > cachegroup in the CZF without any corresponding configuration in > > Traffic Ops, or a cachegroup with configuration in Traffic Ops, but > > with no available caches (DS assignments, health, etc). > > > > Presuming we have configured geolocation coordinates within the CZF, > > we know the lat/long of the cachegroup within the CZF that contains > > the source address. We can then order our list of cachegroups by > > lat/long, then select the "next best" cache group by distance and > > availability. That will be the actual cachegroup to serve the request; > > this prevents a miss on the CZF that would normally be routed to the > > Geolocation service selected for the DS. > > > > We do have a slight gap around logging, and maybe that's part of the > > question. What we see in the log is the selected lat/long, not the > > source lat/long of the hit, so we can't easily tell when we're in this > > case by simply looking at logs. This could be an area of improvement, > > however, we'll need to be careful to not conflate the logs with > > unnecessary information. In most cases the hit is the selected > > cachegroup, so we need to be careful to not just add "source" and > > "actual" coordinates to the log because it'll be identical in most CZF > > hit cases. > > > > Thanks, > > Thanks, > > Jeff > > > > > > On Wed, Mar 29, 2017 at 7:02 AM, John Shen (weifensh) > > <[email protected]> wrote: > >> Hi Jeff, > >> > >> I have just tried the getClosestCacheLocation() logic. It appears the > CZF > >> matched lat/long does come from CZF, but the lat/long of the “closest” > Cache > >> Groups is from the configuration by Ops. This means to calculate the > >> distance from the matched CG and “closest” CG, the source lat/long is > from > >> CZF, but the dest lat/long is not from CZF but from CG settings on Ops. > Is > >> this expected behavior? > >> > >> Thanks, > >> John > >> > >> > >> On 27/01/2017, 10:51 PM, "Jeff Elsloo" <[email protected]> wrote: > >> > >> Steve: I don't think the patch is required, however, as Eric found, > >> without the patch there could be some gaps depending on the > scenario. > >> That specific scenario revolved around the "next best cache group" > not > >> having a DS assigned, or a healthy cache with the DS assigned. In > that > >> case, despite the hits, you would still end up falling through to > the > >> geolocation provider. The patch addresses that. > >> > >> Eric: The rloc field is set via the Geolocation associated with the > >> CacheLocation, which ultimately comes from the edgeLocations section > >> of the CRConfig. When a CZF lookup is performed inside TR, a hit > >> returns a CacheLocation. When caches aren't available within that > >> CacheLocation, getClosestCacheLocation() is called, and that's why > you > >> see the lat/long of the "next best cache group" instead of the > actual > >> hit's lat/long. > >> > >> If we want to have granularity in this situation, we might need to > 1) > >> create a new RestultType, such as ResultType.CZ_NEXT (or something), > >> and/or 2) massage the log format such that we either have a the > >> original lat/long, and new lat/long in the rloc field, or create a > new > >> field to save one or the other, such that we log both lat/longs. > >> > >> Thoughts? Whatever we decide should go into TC-90 so we can apply > the > >> proposed patch and improve the logging. > >> -- > >> Thanks, > >> Jeff > >> > >> > >> On Fri, Jan 27, 2017 at 7:14 AM, Eric Friedrich (efriedri) > >> <[email protected]> wrote: > >> > The rloc field usually indicates the Geolocation IP of the client > >> (short for request location) > >> > > >> > But here it looks like rloc is reflecting the location of the CG > it > >> ultimately redirected to (response location?). > >> > > >> > I would have expected the rloc field to either > >> > 1) be blank (because we never did a lookup from geoprovider) > >> > or > >> > 2) to contain the coordinates of the cache group the CZF hit > on > >> (in this case us-ga-macon at 32.7261, -83.6547”) > >> > > >> > —Eric > >> > > >> >> On Jan 27, 2017, at 8:28 AM, Steve Malenfant < > [email protected]> > >> wrote: > >> >> > >> >> Jeff, > >> >> > >> >> CZF properly installed: yes > >> >> Network address or not: same behavior > >> >> > >> >> But you nailed the API one. There is no cache assigned to > >> us-ga-macon, > >> >> which is exactly what I'm testing. > >> >> > >> >> I added cache groups for my testing in the lab which I assigned a > >> few > >> >> caches to them : > >> >> > >> >> - us-ga-atlanta 34.0362 -84.3207 > >> >> - us-ok-oklahomacity 35.4777 -97.5545 > >> >> - us-va-nova 38.7922 -77.2136 > >> >> - us-ca-sandiego 32.7205 -117.0838 > >> >> > >> >> API : > >> >> > >> {"locationByGeo":{"city":"Macon","countryCode":"US"," > latitude":"32.7288","postalCode":"31216","countryName":"United > >> >> States","longitude":"-83.6865"},"locationByFederation":"not > >> >> found","requestIp":"24.252.192.1","locationByCoverageZone":"not > >> found"} > >> >> > >> >> Using the X-MM-Client-IP it returned the proper cache based on > CZ, > >> it > >> >> correctly sent the request to the cache in us-ga-atlanta : > >> >> 1485522786.423 qtype=HTTP chi=24.252.192.1 url=" > >> >> http://crs.cox-col-jitp2.cdn1.coxlab.net/"; cqhm=GET > cqhv=HTTP/1.1 > >> rtype=CZ > >> >> rloc="34.03,-84.32" rdtl=- rerr="-" rgb="-" pssc=302 ttms=0.260 > >> rurl=" > >> >> http://cdn1cdedge0007.cox-col-jitp2.cdn1.coxlab.net/"; rh="-" > >> >> > >> >> I then changed the coordinate to match the us-ca-sandiego group > in > >> the CZF > >> >> and now the request is sent to the us-ca-sandiego caches : > >> >> 1485523546.345 qtype=HTTP chi=24.252.192.1 url=" > >> >> http://crs.cox-col-jitp2.cdn1.coxlab.net/"; cqhm=GET > cqhv=HTTP/1.1 > >> rtype=CZ > >> >> rloc="32.72,-117.08" rdtl=- rerr="-" rgb="-" pssc=302 ttms=0.206 > >> rurl=" > >> >> http://cdn1cdedge0001.cox-col-jitp2.cdn1.coxlab.net/"; rh="- > >> >> > >> >> I'm using 1.6.1 + patch discussed in this email. Not sure if > those > >> are > >> >> necessary but I'll need to try on unpatched version. > >> >> > >> >> Do we want to fix API to reflect CZF? > >> >> > >> >> Thanks for your help. > >> >> > >> >> Steve > >> >> > >> >> > >> >> > >> >> > >> >> > >> >> > >> >> > >> >> > >> >> On Thu, Jan 26, 2017 at 4:47 PM, Jeff Elsloo > >> <[email protected]> wrote: > >> >> > >> >>> Dave just let me know that in this case you don't have any > caches > >> >>> assigned in us-ga-macon. I'm not sure how the API behaves at > that > >> >>> point – it likely won't follow the same "next best cache group" > >> logic, > >> >>> as it was designed as a simple lookup tool. > >> >>> > >> >>> Can you try simulating a request through Traffic Router directly > >> using > >> >>> the X-MM-Client-IP header, or fakeClientIpAddress query > parameter > >> >>> using the example IP of 24.252.192.0? After you do so, check the > >> >>> coordinates in the log entry and see if the result is a CZ hit. > >> >>> -- > >> >>> Thanks, > >> >>> Jeff > >> >>> > >> >>> > >> >>> On Thu, Jan 26, 2017 at 2:03 PM, Jeff Elsloo > >> <[email protected]> > >> >>> wrote: > >> >>>> Are you 100% sure that the Traffic Router has loaded the > updated > >> CZF? > >> >>>> If so, what happens when you use an IP within the /20 instead > of > >> the > >> >>>> network address (.0)? I tried using a network address of a /22 > on > >> a > >> >>>> 1.8 TR and it hit the CZF as expected. Ultimately what you're > >> seeing > >> >>>> is a CZF miss, unrelated to the geo coordinates. > >> >>>> > >> >>>> The underlying feature with the coordinates is to select the > next > >> best > >> >>>> cache group by proximity where healthy caches have a given > >> delivery > >> >>>> service assigned. In order to test that, you would need to > have a > >> CZF > >> >>>> hit in a cache group which doesn't have that particular > delivery > >> >>>> service assigned to any caches, or have all caches within that > >> cache > >> >>>> group with that delivery service in an unhealthy state. > >> >>>> > >> >>>> Thanks, > >> >>>> -- > >> >>>> Thanks, > >> >>>> Jeff > >> >>>> > >> >>>> > >> >>>> On Wed, Jan 25, 2017 at 1:33 PM, Steve Malenfant > >> <[email protected]> > >> >>> wrote: > >> >>>>> Jeff, > >> >>>>> > >> >>>>> I've tried this coverage zone file coordinate overwrite... I > >> might be > >> >>>>> missing something. > >> >>>>> > >> >>>>> I defined the following : > >> >>>>> > >> >>>>> "us-ga-macon": { > >> >>>>>> "coordinates": { > >> >>>>>> "latitude": "32.7261", > >> >>>>>> "longitude": "-83.6547" > >> >>>>>> }, > >> >>>>>> "network": [ > >> >>>>>> "24.252.192.0/20", > >> >>>>>> "68.1.20.0/22", > >> >>>>> > >> >>>>> > >> >>>>> Then issued the following query : > >> >>>>> > >> >>>>>> curl http://traffic_router:3333/crs/stats/ip/24.252.192.0 > >> >>>>>> > >> >>>>>> {"locationByGeo":{"city":"Macon","countryCode":"US"," > >> >>> latitude":"32.7288","postalCode":"31216","countryName":"United > >> >>>>>> States","longitude":"-83.6865"},"locationByFederation":"not > >> >>>>>> found","requestIp":"24.252.192.0"," > locationByCoverageZone":"not > >> >>> found"} > >> >>>>>> > >> >>>>> I believe I'm expecting "locationByCoverageZone" to find > >> something... > >> >>>>> > >> >>>>> I tried on 1.6.0 and 1.6.1 (patched with the pastebin above > >> which I > >> >>> wasn't > >> >>>>> sure I was suppose to do). > >> >>>>> > >> >>>>> Would you mind giving me some light on this? > >> >>>>> > >> >>>>> Thanks, > >> >>>>> > >> >>>>> Steve > >> >>>>> > >> >>>>> > >> >>>>> On Mon, Jan 23, 2017 at 3:05 PM, Jeff Elsloo > >> <[email protected]> > >> >>> wrote: > >> >>>>> > >> >>>>>> Yes; the feature went into 1.5.x. > >> >>>>>> -- > >> >>>>>> Thanks, > >> >>>>>> Jeff > >> >>>>>> > >> >>>>>> > >> >>>>>> On Thu, Jan 19, 2017 at 10:37 AM, Steve Malenfant < > >> >>> [email protected]> > >> >>>>>> wrote: > >> >>>>>>> I didn't know about this which is good information. Does > that > >> work on > >> >>>>>>> Traffic Router 1.6? > >> >>>>>>> > >> >>>>>>> On Mon, Jan 9, 2017 at 12:44 PM, Eric Friedrich (efriedri) < > >> >>>>>>> [email protected]> wrote: > >> >>>>>>> > >> >>>>>>>> Jeff and I had a quick Slack convo, so I’ll add a followup > >> summary > >> >>> here > >> >>>>>> in > >> >>>>>>>> case anyone else is interested. > >> >>>>>>>> > >> >>>>>>>> Cache Group location (lat/long) is configured in Traffic > Ops > >> today > >> >>> (and > >> >>>>>> is > >> >>>>>>>> used for computing distance from Maxmind Geolocation). > >> >>>>>>>> > >> >>>>>>>> You can also configure the location (lat/long) for a Cache > >> Group in > >> >>> the > >> >>>>>>>> CoverageZone file (example below). > >> >>>>>>>> > >> >>>>>>>> When this location is configured (and Jeff’s suggested > logic > >> fix > >> >>> from > >> >>>>>>>> below is applied) and all caches in the mapped cache group > >> are > >> >>>>>> unavailable, > >> >>>>>>>> TR will send a client request to the cache group that is > >> closest to > >> >>> the > >> >>>>>>>> original mapped group. > >> >>>>>>>> > >> >>>>>>>> Example CZF w/ cache location > >> >>>>>>>> ----- > >> >>>>>>>> "coverageZones": { > >> >>>>>>>> “edge-cg-1": { > >> >>>>>>>> "network6": [ > >> >>>>>>>> ... > >> >>>>>>>> ], > >> >>>>>>>> "network": [ > >> >>>>>>>> ... > >> >>>>>>>> ], > >> >>>>>>>> "coordinates": { > >> >>>>>>>> "longitude": “-75.3342", > >> >>>>>>>> "latitude": “42.555" > >> >>>>>>>> } > >> >>>>>>>> }, > >> >>>>>>>> > >> >>>>>>>> > >> >>>>>>>> —Eric > >> >>>>>>>> > >> >>>>>>>> > >> >>>>>>>>> On Jan 5, 2017, at 12:06 PM, Jeff Elsloo > >> <[email protected]> > >> >>>>>> wrote: > >> >>>>>>>>> > >> >>>>>>>>> If we applied the proposed change, given your scenario we > >> should > >> >>> fall > >> >>>>>>>>> through to the return statement that calls > >> >>> getClosestCacheLocation(). > >> >>>>>>>>> That method will order all cache groups based on their > >> lat/long > >> >>> and > >> >>>>>>>>> the lat/long of the cache group we hit on in the CZF. Once > >> the > >> >>> list is > >> >>>>>>>>> ordered, we iterate through the list until we find a cache > >> group > >> >>> that > >> >>>>>>>>> has available caches for that DS. > >> >>>>>>>>> > >> >>>>>>>>> BTW, the stuff on line 536 is likely to produce the exact > >> same > >> >>> result > >> >>>>>>>>> as the check that precedes it. networkNode.getLoc() will > >> return > >> >>> the > >> >>>>>>>>> string name of the cache group, so when we find the > >> >>> CacheLocation, it > >> >>>>>>>>> will be the same as what we had just checked. We could > >> probably > >> >>> get > >> >>>>>>>>> away with removing that part of the method as it's > >> redundant. > >> >>>>>>>>> -- > >> >>>>>>>>> Thanks, > >> >>>>>>>>> Jeff > >> >>>>>>>>> > >> >>>>>>>>> > >> >>>>>>>>> On Wed, Jan 4, 2017 at 11:54 AM, Eric Friedrich (efriedri) > >> >>>>>>>>> <[email protected]> wrote: > >> >>>>>>>>>> Where would TR look outside the assigned cache group to > >> find the > >> >>> next > >> >>>>>>>> closest cache group? > >> >>>>>>>>>> > >> >>>>>>>>>>> On Jan 4, 2017, at 11:25 AM, Eric Friedrich (efriedri) < > >> >>>>>>>> [email protected]> wrote: > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> On Jan 3, 2017, at 5:20 PM, Jeff Elsloo > >> <[email protected] > >> >>>>>> <mailto: > >> >>>>>>>> [email protected]>> wrote: > >> >>>>>>>>>>> > >> >>>>>>>>>>> Hey Eric, > >> >>>>>>>>>>> > >> >>>>>>>>>>> It sounds like the use case you're after is an RFC 1918 > >> client > >> >>>>>>>>>>> associated with a cache group whose caches are all > >> unavailable > >> >>> for > >> >>>>>> one > >> >>>>>>>>>>> reason or another. Is that correct? > >> >>>>>>>>>>> Yes, exactly. > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> I looked at the code a bit, and I think that we can > make a > >> minor > >> >>>>>>>>>>> change to achieve the behavior you're looking for as > long > >> as > >> >>> you're > >> >>>>>>>>>>> able to put your RFC 1918 ranges in the CZF. > >> >>>>>>>>>>> Yes, we would want those ranges in the CZF. I can’t > think > >> of any > >> >>>>>> other > >> >>>>>>>> place they would go. > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> There's a small logic gap in the existing algorithm > around > >> cache > >> >>>>>>>>>>> location selection and I think if we fix that (two line > >> >>> change), we > >> >>>>>>>>>>> should be better off all around. I think the only time > >> we'd ever > >> >>>>>> want > >> >>>>>>>>>>> to go to the geolocation provider is in the event of a > >> miss on > >> >>> the > >> >>>>>>>>>>> CZF, so as long as we have a hit there, we should find > the > >> cache > >> >>>>>> group > >> >>>>>>>>>>> closest to that hit location that has available caches. > >> This > >> >>> would > >> >>>>>>>>>>> automatically provide the "backup" cache group concept, > >> and has > >> >>> the > >> >>>>>>>>>>> added benefit of doing this selection dynamically based > on > >> the > >> >>> state > >> >>>>>>>>>>> of the CDN. > >> >>>>>>>>>>> Wow, thanks for picking up on this solution. Sounds > like a > >> >>> strong > >> >>>>>>>> possibility. I like that it can extend dynamically. > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> See this to get an idea of what I mean: > >> >>> http://apaste.info/u3PQo > >> >>>>>>>>>>> https://github.com/apache/ > incubator-trafficcontrol/blob/ > >> >>>>>>>> 249bd7504eeb7cc43402126f3719017e2475ad33/traffic_router/ > >> >>>>>>>> core/src/main/java/com/comcast/cdn/traffic_control/ > >> >>>>>>>> traffic_router/core/router/TrafficRouter.java#L536 > >> >>>>>>>>>>> Does this line set cacheLocation to the closest cache > >> group with > >> >>>>>>>> active caches on that DS? > >> >>>>>>>>>>> > >> >>>>>>>>>>> What does networkNode.getLoc() actually return? > >> >>>>>>>>>>> > >> >>>>>>>>>>> —Eric > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> Obviously we'd need to test this to ensure we don't > break > >> other > >> >>>>>>>> functionality. > >> >>>>>>>>>>> -- > >> >>>>>>>>>>> Thanks, > >> >>>>>>>>>>> Jeff > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> On Tue, Jan 3, 2017 at 10:07 AM, Eric Friedrich > (efriedri) > >> >>>>>>>>>>> <[email protected]<mailto:[email protected]>> wrote: > >> >>>>>>>>>>> If all caches in the primary cache group are > unavailable, > >> our > >> >>> goal > >> >>>>>> is > >> >>>>>>>> to provide a backup routing policy for RFC1918 clients. > >> >>>>>>>>>>> > >> >>>>>>>>>>> When client IP is an public Internet IP, the current > >> backup > >> >>> policy > >> >>>>>> is > >> >>>>>>>> to assign the client to the geographically closest cache > >> (Distance = > >> >>>>>>>> MaxMind Geo Lat/Long - configured CG lat/long). > >> >>>>>>>>>>> > >> >>>>>>>>>>> When client IP is an RFC1918 IP, the client would not > have > >> a > >> >>> maxmind > >> >>>>>>>> geo-loc, so would fall back to the DS geo-miss lat long. > We’d > >> prefer > >> >>>>>> some > >> >>>>>>>> more granular control over where these clients are routed > to, > >> rather > >> >>>>>> than a > >> >>>>>>>> per-DS setting. > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> So with an RFC1918 client, the lookup process would be > >> (step 3 > >> >>> is > >> >>>>>> only > >> >>>>>>>> addition) > >> >>>>>>>>>>> 1) Check CZF for a subnet match (and find a match for > >> existing > >> >>> cache > >> >>>>>>>> group). Assign client to CG > >> >>>>>>>>>>> 2) Check CG for available (online and associated w/ DS) > >> >>> servers. In > >> >>>>>>>> this particular case, assume CG has no servers available to > >> route > >> >>> the > >> >>>>>>>> client to > >> >>>>>>>>>>> 3) Walk the CZF's list of backup CGs and perform the > check > >> from > >> >>> #2 > >> >>>>>> for > >> >>>>>>>> each CG. Use first server that is found > >> >>>>>>>>>>> 4) Assuming no server is found in #3, perform > geo-location > >> and > >> >>> find > >> >>>>>>>> closest cache group. Use a server from the closest CG if > one > >> is > >> >>> found > >> >>>>>>>>>>> 4a) If geo-location returns null, use the DS’ default > >> geo-miss > >> >>>>>>>> location as the client location. > >> >>>>>>>>>>> > >> >>>>>>>>>>> —Eric > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> On Dec 26, 2016, at 10:01 AM, Jan van Doorn > >> <[email protected] > >> >>>>>> <mailto: > >> >>>>>>>> [email protected]>> wrote: > >> >>>>>>>>>>> > >> >>>>>>>>>>> Hi Eric, > >> >>>>>>>>>>> > >> >>>>>>>>>>> How does the backup list relate to the > >> RFC1918-is-not-in-geo > >> >>>>>> problem? > >> >>>>>>>>>>> > >> >>>>>>>>>>> To get to a cachegroup you need to get a match in the > >> coverage > >> >>>>>> zone, I > >> >>>>>>>> would think? > >> >>>>>>>>>>> > >> >>>>>>>>>>> Rgds, > >> >>>>>>>>>>> JvD > >> >>>>>>>>>>> > >> >>>>>>>>>>> On Dec 22, 2016, at 12:28, Eric Friedrich (efriedri) < > >> >>>>>>>> [email protected]<mailto:[email protected]>> wrote: > >> >>>>>>>>>>> > >> >>>>>>>>>>> The current behavior of cache group selection works as > >> follows > >> >>>>>>>>>>> 1) Look for a subnet match in CZF > >> >>>>>>>>>>> 2) Use MaxMind/Neustar for GeoLocation based on client > IP. > >> >>> Choose > >> >>>>>>>> closest cache group. > >> >>>>>>>>>>> 3) Use Delivery Service Geo-Miss Lat/Long. Choose > closest > >> cache > >> >>>>>> group. > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> For deployments where IP addressing is primarily private > >> (say > >> >>>>>> RFC-1918 > >> >>>>>>>> addresses), client IP Geo Location (#2) is not useful. > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> We are considering adding another field to the Coverage > >> Zone > >> >>> File > >> >>>>>> that > >> >>>>>>>> configures an ordered list of backup cache groups to try if > >> the > >> >>> primary > >> >>>>>>>> cache group does not have any available caches. > >> >>>>>>>>>>> > >> >>>>>>>>>>> Example: > >> >>>>>>>>>>> > >> >>>>>>>>>>> "coverageZones": { > >> >>>>>>>>>>> "cache-group-01": { > >> >>>>>>>>>>> “backupList”: [“cache-group-02”, “cache-group-03”], > >> >>>>>>>>>>> "network6": [ > >> >>>>>>>>>>> "1234:5678::\/64”, > >> >>>>>>>>>>> "1234:5679::\/64"], > >> >>>>>>>>>>> "network": [ > >> >>>>>>>>>>> "192.168.8.0\/24", > >> >>>>>>>>>>> "192.168.9.0\/24”] > >> >>>>>>>>>>> } > >> >>>>>>>>>>> > >> >>>>>>>>>>> This configuration could also be part of the per-cache > >> group > >> >>>>>>>> configuration, but that would give less control over which > >> clients > >> >>>>>>>> preferred which cache groups. For example, you may have > cache > >> >>> groups in > >> >>>>>> LA, > >> >>>>>>>> Chicago and NY. If the Chicago Cache group fails, you may > >> want some > >> >>> of > >> >>>>>> the > >> >>>>>>>> Chicago clients to go to LA and some to go to NY. If the > >> backup CG > >> >>>>>>>> configuration is per-cg, we would not be able to control > >> where > >> >>> clients > >> >>>>>> are > >> >>>>>>>> allocated. > >> >>>>>>>>>>> > >> >>>>>>>>>>> Looking for opinions and comments on the above proposal, > >> this is > >> >>>>>> still > >> >>>>>>>> in idea stage. > >> >>>>>>>>>>> > >> >>>>>>>>>>> Thanks All! > >> >>>>>>>>>>> Eric > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>> > >> >>>>>>>> > >> >>>>>>>> > >> >>>>>> > >> >>> > >> > > >> > >> > -- *Oren Shemesh* Qwilt | Work: +972-72-2221637| Mobile: +972-50-2281168 | [email protected] <[email protected]>
