Increase maximum ISO size to 20GB in KVMs.

Some Linux distributions, in particular server distributions such
as RHEL or SLE, have ISOs that are above 10GB in size.
This commits updates the maximum ISO size from 10GB to 20GB, so that
these ISOs can be used when requesting a new KVM.

software/kvm/instance-kvm-cluster-input-schema.json

@@ -448,7 +448,7 @@
             },
             "boot-image-url-list": {
               "title": "Boot image list",
-              "description": "The list shall be list of direct URLs to images, followed by hash (#), then by image MD5SUM. Each image shall appear on newline, like: \"https://example.com/image.iso#06226c7fac5bacfa385872a19bb99684<newline>https://example.com/another-image.iso#31b40d58b18e038498ddb46caea1361c\". They will be provided in KVM image list according to the order on the list. After updating the list, the instance has to be restarted to refresh it. Amount of images is limited to 4, and one image can be maximum 10G. Image will be downloaded and checked against its MD5SUM 4 times, then it will be considered as impossible to download with given MD5SUM. Each image has to be downloaded in time shorter than 4 hours, so in case of very slow images to access, it can take up to 16 hours to download all of them. Note: The instance has to be restarted in order to update the list of available images in the VM. Note: Maximum 3 ISOs are supported.",
+              "description": "The list shall be list of direct URLs to images, followed by hash (#), then by image MD5SUM. Each image shall appear on newline, like: \"https://example.com/image.iso#06226c7fac5bacfa385872a19bb99684<newline>https://example.com/another-image.iso#31b40d58b18e038498ddb46caea1361c\". They will be provided in KVM image list according to the order on the list. After updating the list, the instance has to be restarted to refresh it. Amount of images is limited to 4, and one image can be maximum 20GB. Image will be downloaded and checked against its MD5SUM 4 times, then it will be considered as impossible to download with given MD5SUM. Each image has to be downloaded in time shorter than 4 hours, so in case of very slow images to access, it can take up to 16 hours to download all of them. Note: The instance has to be restarted in order to update the list of available images in the VM. Note: Maximum 3 ISOs are supported.",
               "type": "string",
               "textarea": true
             },

software/kvm/instance-kvm-input-schema.json

@@ -311,7 +311,7 @@
     },
     "boot-image-url-list": {
       "title": "Boot image list",
-      "description": "The list shall be list of direct URLs to images, followed by hash (#), then by image MD5SUM. Each image shall appear on newline, like: \"https://example.com/image.iso#06226c7fac5bacfa385872a19bb99684<newline>https://example.com/another-image.iso#31b40d58b18e038498ddb46caea1361c\". They will be provided in KVM image list according to the order on the list. After updating the list, the instance has to be restarted to refresh it. Amount of images is limited to 4, and one image can be maximum 10G. Image will be downloaded and checked against its MD5SUM 4 times, then it will be considered as impossible to download with given MD5SUM. Each image has to be downloaded in time shorter than 4 hours, so in case of very slow images to access, it can take up to 16 hours to download all of them. Note: The instance has to be restarted in order to update the list of available images in the VM. Note: Maximum 3 ISOs are supported.",
+      "description": "The list shall be list of direct URLs to images, followed by hash (#), then by image MD5SUM. Each image shall appear on newline, like: \"https://example.com/image.iso#06226c7fac5bacfa385872a19bb99684<newline>https://example.com/another-image.iso#31b40d58b18e038498ddb46caea1361c\". They will be provided in KVM image list according to the order on the list. After updating the list, the instance has to be restarted to refresh it. Amount of images is limited to 4, and one image can be maximum 20GB. Image will be downloaded and checked against its MD5SUM 4 times, then it will be considered as impossible to download with given MD5SUM. Each image has to be downloaded in time shorter than 4 hours, so in case of very slow images to access, it can take up to 16 hours to download all of them. Note: The instance has to be restarted in order to update the list of available images in the VM. Note: Maximum 3 ISOs are supported.",
       "type": "string",
       "textarea": true
     },

software/kvm/template/image-download-controller.py.in

@@ -98,7 +98,7 @@ if __name__ == "__main__":
         '--location',  # follow redirects
         '--no-progress-meter',  # do not tell too much
         '--max-time', '14400',  # maximum time for download is 4 hours
-        '--max-filesize', '10737418240',  # maximum 10G for an image
+        '--max-filesize', '21474836480',  # maximum 20GB for an image
         '--output', destination_tmp, image['url']],
         stderr=subprocess.STDOUT)
     except subprocess.CalledProcessError as e: