fix: retain QuoteLambdaEIP on stack delete/replace - #487
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Apply RemovalPolicy.RETAIN to the QuoteLambdaElasticIp CfnEIP so both DeletionPolicy and UpdateReplacePolicy render as "Retain". Market makers allowlist this exact egress address; CloudFormation's default releases an EIP back to the public pool on resource removal or stack deletion, which is unrecoverable. No logical-ID or property changes. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
SocksNFlops
approved these changes
Sep 3, 2026
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What
Apply
RemovalPolicy.RETAINto theQuoteLambdaElasticIpCfnEIPinbin/stacks/api-stack.ts, so the synthesizedAWS::EC2::EIPresource carries both:Nothing else changes: same construct ID, same logical ID (
QuoteLambdaElasticIp), same properties. Beta and prod share this code path, so one change covers both stages.Why
This EIP is the service's static egress address. It feeds the NAT gateway of the quote-lambda VPC, so every outbound RFQ webhook call to market makers originates from it. Market makers firewall-allowlist this exact IP; their servers reject RFQ traffic from any other source.
CloudFormation's default behaviour for an
AWS::EC2::EIPwith noDeletionPolicyis to release the allocation back to the public AWS pool whenever the resource is removed from the template or the stack is deleted. A released EIP cannot be reliably recovered, and every market maker would have to re-allowlist a new address. An upcoming migration depends on keeping this exact address, so this PR is the safety net against that failure mode:DeletionPolicy: Retainkeeps the allocation if the resource is removed or the stack is deleted.UpdateReplacePolicy: Retainkeeps the old allocation if a future change ever forces a replacement.A
RemovalPolicychange is metadata-only from CloudFormation's point of view. Applying it does not modify or replace the EIP, so deploying this is a no-op for the live address.Explicitly out of scope
Removing or orphaning the EIP from the stack is not done here. That happens at migration cutover and requires hardcoded allocation IDs on the consuming side. This PR only guarantees that when that step happens, the address survives it.
The three NAT EIPs in the nested
AnalyticsStack(Redshift VPC) are left as-is; nothing external depends on those addresses.Verification
yarn install --frozen-lockfile && yarn buildclean.npx cdk synthfrommainand from this branch into separate output directories, thendiff -uon every*.template.json. The only difference across all templates is the two policy lines above on theQuoteLambdaElasticIpresource inGoudaParameterizationStack.template.json. No logical-ID or property changes, no changes to nested templates or the pipeline stack.yarn lint: 0 errors (86 pre-existing warnings, unchanged).cdk deploywas not run.Reviewer note
Merging to
mainauto-deploys to beta and prod via the CDK pipeline. Please review before merging.🤖 Generated with Claude Code