Reference
Rack Parameters

Setting Parameters

Parameters can be set using the following command.

convox rack params set Foo=bar

You can also set multiple parameters at once.

convox rack params set Foo=bar Baz=qux

Ami

Which Amazon Machine Image should be used.

ApiCount

How many Rack API containers to run. Setting this higher than 2 will guarantee better Rack API availability for mission critical clusters.

| Default value | 2 |

ApiCpu

How much CPU should be reserved by the API web process.

| Default value | 128 |

ApiMemory

How much memory should be reserved by the API web process.

| Default value | 128 |

Autoscale

Autoscale rack instances. See our Scaling doc for more information.

| Default value | Yes | | Allowed values | Yes, No |

AutoscaleExtra

The number of instances of extra capacity that autoscale should keep running.

| Default value | 1 |

AvailabilityZones

Override the default availability zones used in a Rack. Please note that updating this parameter once a Rack is installed will require setting MaxAvailabilityZones to the new AZs quantity you are choosing.

| Default value | |

BuildCpu

How much CPU should be allocated to builds.

| Default value | 0 |

BuildInstance

EC2 instance type to create and use as the Rack’s dedicated build instance.

Note: the build instance will also use the InstanceBootCommand and InstanceRunCommand Rack params, if defined.

| Default value | | | Allowed values | EC2 Instance Types |

See also the InstanceType Rack parameter.

BuildMemory

Defines the amount of memory (in MB) that the instance should allocate to build containers for each build.

| Default value | 1024 |

Getting build errors like Starting build... ERROR: not enough memory available to start process? You should either reduce this parameter, or change the InstanceType parameter to an instance type with more memory.
Note: If you set BuildMemory to an amount that's more than half of the total memory available to the build instance, you'll only be able to run one build at a time. If this value is too high, builds may fail.

BuildVolumeSize

Getting errors like No space left on device on your builds (not your running applications)? You can extend the space on the device by increasing this parameter.

Default container disk size in GB.

| Default value | 100 |

ClientId

Anonymous identifier.

| Default value | dev@convox.com |

EcsPollInterval

How often (in seconds) to poll ECS for service updates(to inject into the app logs.

| Default value | 1 |

EncryptEbs

Enable encryption at rest for EBS volumes.

| Default value | No | | Allowed values | Yes, No |

Encryption

Encrypt secrets with KMS.

| Default value | Yes | | Permitted values | Yes, No |

ExistingVpc

Existing VPC-ID from AWS, if blank a VPC will be created. Additional paramater InternetGateway must be set to use ExistingVPC.

| Default value || | Permitted values |VPC ID|

HighAvailability

This parameter cannot be changed after the rack is created.

Whether or not enable High Availability mode, choose between failure resiliency and cost efficiency. This ensure proper resources redundancy to mitigate system failures.

If HighAvailability is set to true, the InstanceCount is used as initial cluster size. If false, the NoHaInstanceCount is used as initial cluster size. Both can be scaled to 1000 instances.

| Default value | true | | Allowed values | true, false |

HttpProxy

HTTP proxy for outbound HTTP connections (for network-restricted Racks).

Set this value to the hostname (or IP address) and port number of an HTTP proxy to use for the ECS agent to connect to the internet.

| Default value | |

For more information, see HTTP Proxy Configuration in the AWS docs.

The HttpProxyparam will not change how the apps access the internet, the traffic won’t go through the proxy. Only the instances requests will use the proxy for outbound connections, if you want your apps to use the proxy, you have to configure it on the convox.yml:

services:
  web:
    build: .
    port: 3000
    environment:
      - http_proxy=10.0.1.124:8888
      - https_proxy=10.0.1.124:8888
      - HTTP_PROXY=10.0.1.124:8888
      - HTTPS_PROXY=10.0.1.124:8888
      - NO_PROXY=169.254.170.2

IMDSHttpTokens

Set how your instances will access the instance metadata. You can set EC2 instances to use only v2 by setting IMDSHttpTokens as ‘required’, see Configure the instance metadata options.

| Default value | optional | | Allowed values | optional, required |

InstanceBootCommand

A single line of shell script to run (as root) as a cloud-init command early during instance boot.

For more information about using cloud-init with EC2, see the AWS doc Running Commands on Your Linux Instance at Launch. For cloud-init specifics, see “bootcmd” in the doc Run commands on first boot.

The InstanceBootCommand will also apply to any build instance associated with the Rack.

| Default value | |

Example: increase virtual memory

Tell the host EC2 instance to set operating system limits on mmap to 262144 (useful for ElasticSearch):

$ convox rack params set 'InstanceBootCommand="sysctl -w vm.max_map_count=262144"'
Updating parameters... OK

(Note the surrounding single quotes in the above command.)

InstanceCount

The number of EC2 instances in your Rack cluster. This parameter is only used for clusters with HighAvailablity = true.

| Default value | 3 | | Minimum value | 3 |

InstancePolicy

ARN of an additional IAM policy to add to the instance-level role.

| Default value | |

InstanceRunCommand

A single line of shell script to run as a cloud-init command late during instance boot.

For more information about using cloud-init with EC2, see the AWS doc Running Commands on Your Linux Instance at Launch. For cloud-init specifics, see “runcmd” in the doc Run commands on first boot.

The InstanceRunCommand will also apply to any build instance associated with the Rack.

| Default value | |

InstanceType

The type of EC2 instance to run in your Rack cluster.

| Default value | t2.small | | Allowed values | EC2 Instance Types |

See also the BuildInstance Rack parameter.

InstanceUpdateBatchSize

The number of instances to update in a batch.

| Default value | 1 | | Minimum value | 1 |

Internal

Enable the internal load balancer for this Rack. See Internal Services

| Default value | No | | Allowed values | Yes, No |

InternetGateway

If installing rack on existing VPC, you need to pass existing InternetGateway ID attached to the VPC. See ExistingVPC.

| Default value | |

Key

SSH key name for access to cluster instances.

| Default value | |

LoadBalancerIdleTimeout

The idle timeout value for the ALB, in seconds. The valid range is 1-4000 seconds.

| Default value | 3600 |

LogDriver

Log driver used by the rack and services to send logs. Default to CloudWatch. You must provide the SyslogDestination when setting as Syslog. It disable logs if blank.

Attention!! Disabling CloudWatch will impact convox logs and convox rack logs. Use Syslog resource if you still want to use convox logs, see Resource Syslog

| Default value | CloudWatch | | Allowed values | CloudWatch, Syslog, |

LogRetention

Number of days to keep logs (blank for unlimited). Possible values are: 1, 3, 5, 7, 14, 30, 60, 90, 120, 150, 180, 365, 400, 545, 731, 1827, 2192, 2557, 2922, 3288, and 3653. See Logs retention.

| Default value | 7 |

MaxAvailabilityZones

The maximum number of Availability Zones that the cluster should use.

| Default value | 3 | | Allowed values | 2, 3 |

NoHaInstanceCount

The number of EC2 instances in your non High Availability Rack cluster. It’s only used for non high available clusters.

| Default value | 1 | | Minimum value | 1 |

OnDemandMinCount

If using spot instances through the SpotInstanceBid parameter, this configures the minimum number of on demand instances. This should be set to a value that will guarantee the minimum acceptable service availability. You must set it even if you using the HighAvailability as false, as this will be used to create the minimum on demand instances.

| Default value | 3 |

Password

(REQUIRED) API HTTP password.

| Minimum length | 1 | | Maximum length | 50 |

Private

Have the Rack create non-publicly routable resources, i.e. in a private subnet. See our Private Networking doc for more information.

| Default value | No | | Allowed values | Yes, No |

PrivateApi

Put Rack API Load Balancer in a private network, i.e. have the Rack API use an Internal ELB, making it unreachable from the internet.

| Default value | No | | Allowed values | Yes, No |

PrivateApiSecurityGroup

Specify a custom security group that can connect to the Rack API when PrivateApi=Yes.

| Default value | |

PrivateBuild

Place only the build instances into a private network (unused if Private is Yes)

| Default value | No | | Allowed values | Yes, No |

RouterMitigationMode

Determines how the load balancer handles requests that might pose a security risk to your application. See here for more information.

| Default value | defensive | | Allowed values | defensive, monitor, strictest |

RouterSecurityGroup

Specify a custom security group to use for the Rack’s router.

| Default value | |

ScheduleRackScaleDown & ScheduleRackScaleUp

Use ScheduleRackScaleDown & ScheduleRackScaleUp if you want to turn the rack on/off based on a schedule. Keep in mind that both parameters need to be set. To turn your rack off on weekends and back on during weekdays you can use:

convox rack params set ScheduleRackScaleDown="0 18 * * 5" ScheduleRackScaleUp="0 9 * * 1"

The supported cron expression format consists of five fields separated by white spaces: [Minute] [Hour] [Day_of_Month] [Month_of_Year] [Day_of_Week]. In the example above it’s configured to shutdown every Friday (5th day) at 6pm (UTC). More details on the CRON format can be found in Crontab and examples.

You can see details about the Scheduling Actions on AWS doc.

| Default value | |

SpotInstanceBid

A value, in dollars, that you want to pay for spot instances. If spot instances are available for the bid price, the Rack instances will use spot instances instead of on demand instances, resulting in significant cost savings. If the parameter is empty, spot instances will not be utilized. This must be used with the OnDemandMinCount parameter to guarantee some on demand instances are running if spot instances are not available (even if the HighAvailability is false, if not set will use the default).

| Default value | |

SslPolicy

Specify an SSL policy for the primary Rack load balancer.

| Default value | | | Allowed values | ELB SSL Policies |

Subnet0CIDR

Public Subnet 0 CIDR Block.

| Default value | 10.0.1.0/24 |

Subnet1CIDR

Public Subnet 1 CIDR Block.

| Default value | 10.0.2.0/24 |

Subnet2CIDR

Public Subnet 2 CIDR Block.

| Default value | 10.0.3.0/24 |

SubnetPrivate0CIDR

Private Subnet 0 CIDR Block.

| Default value | 10.0.4.0/24 |

SubnetPrivate1CIDR

Private Subnet 1 CIDR Block.

| Default value | 10.0.5.0/24 |

SubnetPrivate2CIDR

Private Subnet 2 CIDR Block.

| Default value | 10.0.6.0/24 |

SwapSize

Default swap volume size in GB. Set this value to 0 to disable swap.

| Default value | 5 |

SyslogDestination

Syslog address destination, you need to pass the protocol to be used, e.g. tcp+tls://logsX.syslog.com:1234.

| Default value | |

SyslogFormat

Syslog format (low case) to sent to SyslogDestination. See Docker Syslog and RFC5424.

| Default value | rfc5424 |

Tenancy

Dedicated hardware.

| Default value | default | | Allowed values | default, dedicated |

Version

(REQUIRED) Convox release version.

| Minimum length | 1 |

VolumeSize

Default disk size (in gibibytes) of the EBS volume attached to each EC2 instance in the cluster.

| Default value | 50 |

VPCCIDR

VPC CIDR Block. Note that changing this has no effect since VPC CIDR ranges cannot be changed after they’re created.

| Default value | 10.0.0.0/16 |