The number of private networks (internal networks for the instances) is limited by the fact that the curl requests that instances make (i.e. curl -I http://<server IP>/2009-04-04/meta-data/instance-id/) returns the ENTIRE list of networks, and at a certain point this exceed the 8190 URI length limit for apache (which neutron-metadata-agent uses as webserver backend).
Here is the URI that the metadata curl request generates on the OpenStack side in case:
The problem description:
The number of private networks (internal networks for the instances) is limited by the fact that the curl requests that instances make (i.e. curl -I http://<server IP>/2009- 04-04/meta- data/instance- id/) returns the ENTIRE list of networks, and at a certain point this exceed the 8190 URI length limit for apache (which neutron- metadata- agent uses as webserver backend).
Here is the URI that the metadata curl request generates on the OpenStack side in case:
/v2.0/ports. json?network_ id=ce1dc3ce- 6a23-4067- b97b-2d774b95a3 8e&network_ id=108fef5f- fcaa-4c61- a9eb-0aed4ca276 38&network_ id=ce1e0a35- bddf-46b2- a6e4-a285310ee2 7b&network_ id=7329c284- 69c5-4085- 8c4b-a423968f27 7c&network_ id=25d51663- 2aca-4cfd- 8351-ebb6fe6ac2 1e&network_ id=47968396- 8dcf-45d2- b7ca-7b14277960 6b&network_ id=f1d8fcc5- 74dd-4e45- 897f-acfc349bf2 14&network_ id=ab868487- 0b8f-4f2d- 9fa7-07cef6a4d0 8c&network_ id=d6c62b22- 46b7-4bf6- 9973-12c7366ee0 aa&network_ id=13d809ad- 34e9-4c7e- a89e-3b1d0ad465 16&network_ id=9a45b6af- 98c2-41da- 9742-0f1be9653a 7f&network_ id=cd4ebaea- 9437-4ed1- 834d-6ba1285f45 8e&network_ id=7ad5b66b- c913-429f- 9608-0df761d4a1 c0&network_ id=1cc8e42f- f8d7-47cc- 89a9-0841933885 29&network_ id=eaa69786- f63c-4576- 9798-f6e6e1781b 77&network_ id=4f24a32a- 5066-4dfd- 9564-bb0175ba39 8a&network_ id=f82890ec- 4422-499d- b9b2-991c4db133 a7&network_ id=d18aa4b6- 4336-4813- 876a-b1e0360206 91&network_ id=e767f01a- 3874-4cbd- 95c9-821cb597e5 84&network_ id=00fb2bef- fd6d-4bd7- afd2-21b792f2d3 27&network_ id=54234780- 1867-4aca- 8c84-9da17f57fb 64&network_ id=d5fc9a5b- b211-40a9- 9a10-80132a59ab f9&network_ id=3eeb9b41- c7ee-4b92- bb0e-fcee30877e 6b&network_ id=7cf2db1f- 0b45-42fc- acf1-e1e5f7d37f 9a&network_ id=7c0f8b11- e6b6-4d0a- 9b75-62a849c310 d4&network_ id=58af0513- 8ab2-4dc8- 8303-3f75f0ee19 15&network_ id=e37fd173- 71a9-4c85- b15c-a0b43173bc be&network_ id=a1bcf2d1- 1dee-45dc- 8554-6776197609 b8&network_ id=8867cc58- 044a-4f43- aea9-0c3616509c 14&network_ id=f453ba4a- 68f1-4e78- 9ee9-f6236b1e26 cd&network_ id=eef09a5e- 6c38-4ae9- 9375-d4dffce964 65&network_ id=caeb38af- bd77-48bd- bc7a-54267d15d3 86&network_ id=20209828- 2b66-4d6d- a6ed-11bbe97ae2 f7&network_ id=8ce7b415- eede-4d84- bcc8-5b5342560b 05&network_ id=8883efbf- 5a07-4c95- b140-85e038c2f8 fe&network_ id=5a5fb19d- 8fc3-483c- 9d17-fbe011849a 46&network_ id=dfc92ac5- 9d2a-4e98- b08c-d40765e0f8 a3&network_ id=966a9801- c42a-4b36- a959-d74d7b355d 03&network_ id=47994b11- 9f14-4708- bc1a-7adc98d4c0 e1&network_ id=fd48c2d2- bb7d-4886- a890-6f23a3ecdc a9&network_ id=5b19cee1- 8c91-4fda- 9d0d-6f6ba6632f 56&network_ id=bc50eada- 2419-4bd2- 80d2-86ccd9e126 6c&network_ id=51bfc8c3- c06a-4ed6- a492-cf55d380ac 33&network_ id=fb58fce6- be4a-4a46- 89a3-bf1ff9ace9 54&network_ id=7892b3d2- 216a-4ea3- a45b-f1311180c6 38&network_ id=f32e446b- 1a56-42cd- 8fe3-9ecae6405b ef&network_ id=53c8eff9- 2657-4a7f- b02a-f86b28411e ec&network_ id=710af1e4- 27af-4393- b46d-30c6e6dbb6 06&network_ id=9e94f25b- e49e-4804- a784-f4c325e727 ae&network_ id=03933632- a885-474b- acd7-a980ef1120 e3&network_ id=fabac2ac- ffea-4d1c- 8f85-7856a84664 1f&network_ id=bfb0570c- 84b8-4c2e- ba62-f011d19505 91&network_ id=8ef1ccf3- c11c-4010- b6ed-f599d97fb5 65&network_ id=ac3b8389- 45d9-4a3b- 9188-1059912c85 65&network_ id=65704511- 430c-4760- a78a-21c7b0a1dd 2c&network_ id=19e16f27- d69f-4d4b- 8487-6a7b6d468e b9&network_ id=0512afdb- 4e54-4bb8- abc7-793975734b b1&network_ id=1d2bcb94- 1a25-4bbb- 88c2-d946d3acc3 af&network_ id=6e53d931- b036-46fc- b849-81263f11ac a7&network_ id=56225598- 96ec-4d48- b702-a38c9bf6be c5&network_ id=312c22f3- 1291-4885- bdf9-079cfc2f76 6b&network_ id=cc3083f7- f552-44ac- bad7-7a7e9e880f cb&network_ id=10d618bc- 0745-4294- be19-2a353756e7 8d&network_ id=24716fa2- 2680-4ca9- b026-e2b4b2fd5d 08&network_ id=8850aafc- ace8-4ac8- 87aa-6de25cf655 7c&network_ id=506a1e17- b2e8-4571- acba-af300c4ccf 29&network_ id=e1233e15- f839-478f- 9328-9c6ceb1e0e 4b&network_ id=a6c778a5- adf0-4f8f- 8460-ead0c96362 06&network_ id=ae50ed79- 221b-4817- b456-82ef1e1285 bb&network_ id=6192fad1- 82ee-4a24- 8b6f-c1bbfa62a0 e8&network_ id=b37e679d- 4e96-47d2- b52c-44cb257081 32&network_ id=6f5146db- cfa4-4ab4- 840f-06345a0364 01&network_ id=659672a1- c0d5-408a- 9929-a5c5759ec0 bf&network_ id=45de56b1- 2691-409b- a6d0-8a8ba3e16a c6&network_ id=9625b113- 3a47-441c- a3ea-a649e0274c 0f&network_ id=b29a85eb- 05cc-4f10- aace-fd035b9d49 bf&network_ id=71a110d7- 72a1-4a89- 9df5-b5df6d4417 94&network_ id=eca28062- 3779-4b4f- 95f2-d97eb20def 56&network_ id=ef65f55b- a908-4777- bbc5-99e821be0c 33&network_ id=604edad9- 4201-47f9- 8cad-ecdd1c2379 73&network_ id=35d74d36- f379-4902- 9560-112845d64c ba&network_ id=c47b771d- 24d9-491f- af81-fc7451b0a9 a9&network_ id=3643b5ac- 7867-4d72- b7a8-95b623c510 0b&network_ id=15520eff- 7cd3-4baf- a9e2-7a159e0a96 87&network_ id=8c3e6c37- 5067-4b06- b647-07d92faa37 1f&network_ id=8dba215d- 5b8e-4811- 9a72-dfe4a2a299 f7&network_ id=a8cf7931- ec7f-4a66- bdf0-62dd1f89a7 76&network_ id=e867f27d- 8e7d-4c18- 8bd4-aa16358e3a 84&network_ id=fbe785dd- 96ce-45b5- a21c-f07a5bfd6a 49&network_ id=cc8d3030- 363f-46d1- b60d-fd493a4bf3 99&network_ id=1b2afb06- 6e3d-417d- 9b51-5da7694c56 68&network_ id=b7d250ef- 43a6-4486- 83a4-5d52d28fd1 84&network_ id=03a2a12b- 9e1a-4f1d- 9230-29d79bdaec 8a&network_ id=a14a8cc3- 745c-4bbe- 97a8-a62196d193 09&network_ id=4918e2b1- ecab-4460- a004-006cf87059 9d&network_ id=5d5d670d- b2a2-4c0f- a402-6b7b065722 67&network_ id=1afeabda- 6b11-4d07- a38c-b8c8f45fd1 f2&network_ id=b84e4ee9- 48c6-404c- bc3c-9d70d861c1 d3&network_ id=ade51ab2- beda-42a1- a5a5-50485bfdfb 20&network_ id=89c0e381- bbdf-4651- 99f5-3c021e775b 41&network_ id=527f6f7d- c579-496e- b9da-b2892dae2a 91&network_ id=cbd928ac- a364-4ad0- b3d7-45d11bbd07 39&network_ id=e91cd98e- 7857-4cab- 9c9e-c15e0d0698 8e&network_ id=cf52f6b6- 5beb-4ef6- 8338-b3ec342e6c be&network_ id=e061ef26- 3efc-4127- 87bc-03ae766bb6 cb&network_ id=560bb600- bb71-4360- 93de-9f5a86c509 f4&network_ id=0820adfb- 047f-4f78- affe-0e4e0cb672 a2&network_ id=465b64f9- 0dc9-4512- b20e-1ae3bd0055 3f&network_ id=46ca8b2e- 2fae-4e56- 92bc-686b9722dd 8c&network_ id=96839919- c0b7-44a8- 8f62-f4456758dd 96&network_ id=9af448bd- a978-4d9d- 83b8-40b57da2f9 e4&network_ id=778818eb- 9a73-4da5- 9c6b-ccc304c63d 5f&network_ id=15f7b3c9- c45b-44dc- bd16-92c8aff91a 5e&network_ id=2f35ef62- 86d5-4985- b86b-ca444b5d48 18&network_ id=361f0946- c488-4a72- 9338-6168f5c8bd 26&network_ id=3f7b6859- c2e2-4ceb- 8250-2106d2673e 82&network_ id=91f91a5a- 0524-4bd7- bcb1-9bfc897129 56&network_ id=fcf5f676- 8c02-46a8- 977b-f0c0410432 87&network_ id=2dc791e1- c12c-4d68- a8b8-2b5589e759 74&network_ id=c6a761c6- cba4-4248- 9829-e1e903a3d3 b5&network_ id=601cee06- afcf-47e2- a3d3-75247aac40 22&network_ id=932b404c- 0f14-433b- 8ba6-9a311007e1 b9&network_ id=0f82a7e5- 294d-41d2- 833d-cc69c0564e 71&network_ id=1b2e4d2b- 4e71-4131- 87af-a71ce7c1ff 36&network_ id=4089c593- ef6d-4331- b3bf-67b56f371e 08&network_ id=5d69a9d4- 6517-4b62- ab6e-f39e9eb119 a0&network_ id=878ee765- bc99-41c7- a5fe-e31bfe0b53 39&network_ id=b9a15848- 0759-4ca7- ad2a-8ab5aeab28 98&network_ id=e5211cb8- 61cc-4f6b- bbae-7f249cf753 bd&network_ id=435d5e91- 75ed-479c- bd9d-0674945fb8 be&network_ id=6ae531c9- d1a7-495f- 9bed-c221ae0e5c 8b&network_ id=d116c6e1- 2573-47b6- 81bf-0540b8bc7e b0&network_ id=90aa5157- d1be-41ae- 9270-a01693b016 53&network_ id=39994e95- fe11-4878- 8811-87e9afd855 48&network_ id=76b563ae- 4f1e-4a2e- 8f96-ac80a59b16 9d&network_ id=11d78a66- ca5c-40ad- abca-9c6c0dfd75 da&network_ id=cbf71b5f- d894-46a2- 9567-f4341df5c8 e3&network_ id=f5f015d6- 44e1-454e- 89b6-3f04c9c63b 06&network_ id=f6f2fdc3- 2692-4cfe- a356-7743fe785a 7a&network_ id=3165e8c0- 3e7d-428b- 845a-e9481c7ae7 b0&network_ id=ae04bc3f- 75a5-4ae8- a3ae-a6042f4a3c a4&network_ id=b5f492a4- b6d1-4e20- 8649-e4547febdf 22&network_ id=7d52efaa- 76ae-41a1- bb28-4b1c92a880 2f&network_ id=3d381bf9- f8a3-4b70- 8780-0e0b45ded0 3a&network_ id=60548a6f- ed01-4c3a- b9e7-00d6e67b1d 35&network_ id=b35437a5- 0400-40ac- 94ec-7661e53f1a 62&network_ id=f3c7bd67- a3f0-458d- 97aa-fd6e339eac 7c&network_ id=50e1342e- f936-4073- 9ba5-c669593df0 b7&network_ id=b2222aba- f416-4684- 8ff7-2e96a8ec0b f8&network_ id=a05d8b59- 5d07-4cb4- a31e-9016a516b4 85&network_ id=9165faa6- ee87-4b5f- 9b9c-f4610bc19d f7&network_ id=a0856fc7- 0328-4bf7- 9da7-0503a024b9 c6&network_ id=7b6025b6- 1196-4b6a- 8a05-9b53ed92eb ba&network_ id=cddc61d2- ae24-484c- 9508-2d628a8019 ee&network_ id=5978f660- 8353-4be6- 859b-3637b3a870 90&network_ id=8b98dfd8- 4685-4093- 9944-32f3e1e812 45&network_ id=532bb319- e78f-4e88- 98b3-37bc7d0c54 76&network_ id=1b84bffa- 0625-4fe1- b563-204bd92205 6c&network_ id=764824d9- 9e55-4032- a433-8cbd306c75 07&network_ id=ca472d10- a27d-4d07- a704-0c77096925 a2&network_ id=abb59c35- 3a6d-4062- bc56-618b3e6826 da&network_ id=540f26ff- 3fb9-4498- 9874-90dca92f0f a4&network_ id=6ccb6ac4- be6f-461a- 9cb9-ce37c02bd9 c8&network_ id=eb65a45a- 22e9-46b8- bb61-9fc0562288 6d&network_ id=7a87f7e6- 1dc6-4bd1- b737-8baa458bc3 d2&network_ id=e7fcb223- 941d-499e- a390-97a120d4fb 54&network_ id=d927261b- 8405-40c4- 91b7-26d3b17572 0c&network_ id=dce6ebb4- b1e2-498a- bf01-53d92ea626 85&network_ id=9cea528a- 4dcc-48b4- b062-5ed50b0eed 53&network_ id=eedda88a- 4eb7-4640- 8efa-9318cda159 57&network_ id=3482ad24- 1e4d-427b- a90f-ee9b1def59 6c&network_ id=0f502647- a700-4e23- b3e4-f10537ca38 04&network_ id=296aadee- 7961-4a8d- b870-9578b0b2d2 e5&network_ id=a154e040- 5c0b-42ac- 9c06-096fa4d2d1 b9&network_ id=0b1ffdf8- 1f4e-4d15- b6be-3065be9cda 0a&network_ id=98ed63be- b697-4824- b83d-238c558910 aa&fixed_ ips=ip_ address% 3D10.0. 45.2
As you can see, it’s super long, 8497 characters, this breaks Apache.
Similar case - URI too long; but for security groups https:/ /bugs.launchpad .net/python- neutronclient/ +bug/1271462
For this bug fix was applied: https:/ /review. openstack. org/#/c/ 95990/
Basically - (from code) ‘# 1 char of extra URI len will cause a split in 2 requests’ (https:/ /review. openstack. org/#/c/ 95990/3/ neutronclient/ tests/unit/ test_cli20_ securitygroup. py)
I believe there are more clients, which do not support request splitting by length.