Today if we detect concurrent modification of a snapshot repository then we mark it with `CORRUPTED_REPO_GEN` which blocks further writes to try and prevent additional damage to its contents. You can remove the marker by calling the register-repository API again, but this API will discard no-op re-registrations without taking any action. You can work around this by unregistering the repository first (which may be impossible if it's still in use for searchable snapshots) or by re-registering it with some trivial setting change (which seems hacky).

We should not consider it a no-op re-registration if the repository is currently marked with `CORRUPTED_REPO_GEN`, because doing this re-registration will re-read the repo contents and clear the corruption marker and therefore is not a no-op.
server/src/main/java/org/elasticsearch/repositories/RepositoriesService.java
return;
                                    }
                                    delegatedListener.onResponse(verifyResponse);
                                })
                            )
                        );
                    } catch (Exception e) {
                        threadPool.executor(ThreadPool.Names.SNAPSHOT).execute(() -> {
                            try {
                                repository.endVerification(verificationToken);
                            } catch (Exception inner) {
                                inner.addSuppressed(e);
                                logger.warn(() -> "[" + repositoryName + "] failed to finish repository verification", inner);
                            }
                            listener.onFailure(e);
                        });
                    }
                } else {
                    listener.onResponse(Collections.emptyList());
                }
            }
        });
    }
    public static boolean isDedicatedVotingOnlyNode(Set<DiscoveryNodeRole> roles) {
        return roles.contains(DiscoveryNodeRole.MASTER_ROLE)
            && roles.stream().noneMatch(DiscoveryNodeRole::canContainData)
            && roles.contains(DiscoveryNodeRole.VOTING_ONLY_NODE_ROLE);
    }
    /**
     * Checks if new repositories appeared in or disappeared from cluster metadata and updates current list of