* Add cli flag for HTTP API token path (VC)
* Add http_token_path_flag test
* Add pre-check for directory case & Fix test utils
* Update docs
* Apply review: move http_token_path into validator_http_api config
* Lint
* Make diff lesser to replace PK_FILENAME
* Merge branch 'unstable' into feature/cli-token-path
* Applt review: help_vc.md
Co-authored-by: chonghe <44791194+chong-he@users.noreply.github.com>
* Fix help for cli
* Fix issues on ci
* Merge branch 'unstable' into feature/cli-token-path
* Merge branch 'unstable' into feature/cli-token-path
* Merge branch 'unstable' into feature/cli-token-path
* Merge branch 'unstable' into feature/cli-token-path
* Rework Validator Client fallback mechanism
* Add CI workflow for fallback simulator
* Tie-break with sync distance for non-synced nodes
* Fix simulator
* Cleanup unused code
* More improvements
* Add IsOptimistic enum for readability
* Use configurable sync distance tiers
* Fix tests
* Combine status and health and improve logging
* Fix nodes not being marked as available
* Fix simulator
* Fix tests again
* Increase fallback simulator tolerance
* Add http api endpoint
* Fix todos and tests
* Update simulator
* Merge branch 'unstable' into vc-fallback
* Add suggestions
* Add id to ui endpoint
* Remove unnecessary clones
* Formatting
* Merge branch 'unstable' into vc-fallback
* Merge branch 'unstable' into vc-fallback
* Fix flag tests
* Merge branch 'unstable' into vc-fallback
* Merge branch 'unstable' into vc-fallback
* Fix conflicts
* Merge branch 'unstable' into vc-fallback
* Remove unnecessary pubs
* Simplify `compute_distance_tier` and reduce notifier awaits
* Use the more descriptive `user_index` instead of `id`
* Combine sync distance tolerance flags into one
* Merge branch 'unstable' into vc-fallback
* Merge branch 'unstable' into vc-fallback
* wip
* Use new simulator from unstable
* Fix cli text
* Remove leftover files
* Remove old commented code
* Merge branch 'unstable' into vc-fallback
* Update cli text
* Silence candidate errors when pre-genesis
* Merge branch 'unstable' into vc-fallback
* Merge branch 'unstable' into vc-fallback
* Retry on failure
* Merge branch 'unstable' into vc-fallback
* Merge branch 'unstable' into vc-fallback
* Remove disable_run_on_all
* Remove unused error variant
* Fix out of date comment
* Merge branch 'unstable' into vc-fallback
* Remove unnecessary as_u64
* Remove more out of date comments
* Use tokio RwLock and remove parking_lot
* Merge branch 'unstable' into vc-fallback
* Formatting
* Ensure nodes are still added to total when not available
* Allow VC to detect when BN comes online
* Fix ui endpoint
* Don't have block_service as an Option
* Merge branch 'unstable' into vc-fallback
* Clean up lifetimes and futures
* Revert "Don't have block_service as an Option"
This reverts commit b5445a09e9.
* Merge branch 'unstable' into vc-fallback
* Merge branch 'unstable' into vc-fallback
* Improve rwlock sanitation using clones
* Merge branch 'unstable' into vc-fallback
* Drop read lock immediately by cloning the vec.
* Reduce frequency of polling unknown validators.
* Move slot calculation into for loop.
* Simplify logic.
Co-authored-by: Michael Sproul <micsproul@gmail.com>
* Fix formatting
* multiple broadcast flags
* rewrite with single --broadcast option
* satisfy cargo fmt
* shorten sync-committee-messages
* fix a doc comment and a test
* use strum
* Add broadcast test to simulator
* bring --disable-run-on-all flag back with deprecation notice
## Issue Addressed
#4531
## Proposed Changes
add SSZ support to the following block production endpoints:
GET /eth/v2/validator/blocks/{slot}
GET /eth/v1/validator/blinded_blocks/{slot}
## Additional Info
i updated a few existing tests to use ssz instead of writing completely new tests
## Issue Addressed
On a new network a user might require importing validators before waiting until genesis has occurred.
## Proposed Changes
Starts the validator client http api before waiting for genesis
## Additional Info
cc @antondlr
## Issue Addressed
Addresses #2557
## Proposed Changes
Adds the `lighthouse validator-manager` command, which provides:
- `lighthouse validator-manager create`
- Creates a `validators.json` file and a `deposits.json` (same format as https://github.com/ethereum/staking-deposit-cli)
- `lighthouse validator-manager import`
- Imports validators from a `validators.json` file to the VC via the HTTP API.
- `lighthouse validator-manager move`
- Moves validators from one VC to the other, utilizing only the VC API.
## Additional Info
In 98bcb947c I've reduced some VC `ERRO` and `CRIT` warnings to `WARN` or `DEBG` for the case where a pubkey is missing from the validator store. These were being triggered when we removed a validator but still had it in caches. It seems to me that `UnknownPubkey` will only happen in the case where we've removed a validator, so downgrading the logs is prudent. All the logs are `DEBG` apart from attestations and blocks which are `WARN`. I thought having *some* logging about this condition might help us down the track.
In 856cd7e37d I've made the VC delete the corresponding password file when it's deleting a keystore. This seemed like nice hygiene. Notably, it'll only delete that password file after it scans the validator definitions and finds that no other validator is also using that password file.
## Issue Addressed
NA
## Proposed Changes
Adds the `--validator-registration-batch-size` flag to the VC to allow runtime configuration of the number of validators POSTed to the [`validator/register_validator`](https://ethereum.github.io/beacon-APIs/?urls.primaryName=dev#/Validator/registerValidator) endpoint.
There are builders (Agnostic and Eden) that are timing out with `regsiterValidator` requests with ~400 validators, even with a 9 second timeout. Exposing the batch size will help tune batch sizes to (hopefully) avoid this.
This PR should not change the behavior of Lighthouse when the new flag is not provided (i.e., the same default value is used).
## Additional Info
NA
This PR adds the ability to read the Lighthouse logs from the HTTP API for both the BN and the VC.
This is done in such a way to as minimize any kind of performance hit by adding this feature.
The current design creates a tokio broadcast channel and mixes is into a form of slog drain that combines with our main global logger drain, only if the http api is enabled.
The drain gets the logs, checks the log level and drops them if they are below INFO. If they are INFO or higher, it sends them via a broadcast channel only if there are users subscribed to the HTTP API channel. If not, it drops the logs.
If there are more than one subscriber, the channel clones the log records and converts them to json in their independent HTTP API tasks.
Co-authored-by: Michael Sproul <micsproul@gmail.com>
## Issue Addressed
Closes https://github.com/sigp/lighthouse/issues/4291, part of #3613.
## Proposed Changes
- Implement the `el_offline` field on `/eth/v1/node/syncing`. We set `el_offline=true` if:
- The EL's internal status is `Offline` or `AuthFailed`, _or_
- The most recent call to `newPayload` resulted in an error (more on this in a moment).
- Use the `el_offline` field in the VC to mark nodes with offline ELs as _unsynced_. These nodes will still be used, but only after synced nodes.
- Overhaul the usage of `RequireSynced` so that `::No` is used almost everywhere. The `--allow-unsynced` flag was broken and had the opposite effect to intended, so it has been deprecated.
- Add tests for the EL being offline on the upcheck call, and being offline due to the newPayload check.
## Why track `newPayload` errors?
Tracking the EL's online/offline status is too coarse-grained to be useful in practice, because:
- If the EL is timing out to some calls, it's unlikely to timeout on the `upcheck` call, which is _just_ `eth_syncing`. Every failed call is followed by an upcheck [here](693886b941/beacon_node/execution_layer/src/engines.rs (L372-L380)), which would have the effect of masking the failure and keeping the status _online_.
- The `newPayload` call is the most likely to time out. It's the call in which ELs tend to do most of their work (often 1-2 seconds), with `forkchoiceUpdated` usually returning much faster (<50ms).
- If `newPayload` is failing consistently (e.g. timing out) then this is a good indication that either the node's EL is in trouble, or the network as a whole is. In the first case validator clients _should_ prefer other BNs if they have one available. In the second case, all of their BNs will likely report `el_offline` and they'll just have to proceed with trying to use them.
## Additional Changes
- Add utility method `ForkName::latest` which is quite convenient for test writing, but probably other things too.
- Delete some stale comments from when we used to support multiple execution nodes.
It is a well-known fact that IP addresses for beacon nodes used by specific validators can be de-anonymized. There is an assumed risk that a malicious user may attempt to DOS validators when producing blocks to prevent chain growth/liveness.
Although there are a number of ideas put forward to address this, there a few simple approaches we can take to mitigate this risk.
Currently, a Lighthouse user is able to set a number of beacon-nodes that their validator client can connect to. If one beacon node is taken offline, it can fallback to another. Different beacon nodes can use VPNs or rotate IPs in order to mask their IPs.
This PR provides an additional setup option which further mitigates attacks of this kind.
This PR introduces a CLI flag --proposer-only to the beacon node. Setting this flag will configure the beacon node to run with minimal peers and crucially will not subscribe to subnets or sync committees. Therefore nodes of this kind should not be identified as nodes connected to validators of any kind.
It also introduces a CLI flag --proposer-nodes to the validator client. Users can then provide a number of beacon nodes (which may or may not run the --proposer-only flag) that the Validator client will use for block production and propagation only. If these nodes fail, the validator client will fallback to the default list of beacon nodes.
Users are then able to set up a number of beacon nodes dedicated to block proposals (which are unlikely to be identified as validator nodes) and point their validator clients to produce blocks on these nodes and attest on other beacon nodes. An attack attempting to prevent liveness on the eth2 network would then need to preemptively find and attack the proposer nodes which is significantly more difficult than the default setup.
This is a follow on from: #3328
Co-authored-by: Michael Sproul <michael@sigmaprime.io>
Co-authored-by: Paul Hauner <paul@paulhauner.com>
## Issue Addressed
Addresses #4117
## Proposed Changes
See https://github.com/ethereum/keymanager-APIs/pull/58 for proposed API specification.
## TODO
- [x] ~~Add submission to BN~~
- removed, see discussion in [keymanager API](https://github.com/ethereum/keymanager-APIs/pull/58)
- [x] ~~Add flag to allow voluntary exit via the API~~
- no longer needed now the VC doesn't submit exit directly
- [x] ~~Additional verification / checks, e.g. if validator on same network as BN~~
- to be done on client side
- [x] ~~Potentially wait for the message to propagate and return some exit information in the response~~
- not required
- [x] Update http tests
- [x] ~~Update lighthouse book~~
- not required if this endpoint makes it to the standard keymanager API
Co-authored-by: Paul Hauner <paul@paulhauner.com>
Co-authored-by: Jimmy Chen <jimmy@sigmaprime.io>
## Issue Addressed
NA
## Proposed Changes
Adds a service which periodically polls (11s into each mainnet slot) the `node/version` endpoint on each BN and roughly measures the round-trip latency. The latency is exposed as a `DEBG` log and a Prometheus metric.
The `--latency-measurement-service` has been added to the VC, with the following options:
- `--latency-measurement-service true`: enable the service (default).
- `--latency-measurement-service`: (without a value) has the same effect.
- `--latency-measurement-service false`: disable the service.
## Additional Info
Whilst looking at our staking setup, I think the BN+VC latency is contributing to late blocks. Now that we have to wait for the builders to respond it's nice to try and do everything we can to reduce that latency. Having visibility is the first step.
## Issue Addressed
Resolves#2521
## Proposed Changes
Add a metric that indicates the next attestation duty slot for all managed validators in the validator client.
## Issue Addressed
#3780
## Proposed Changes
Add error reporting that notifies the node operator that the `voting_keystore_path` in their `validator_definitions.yml` file may be incorrect.
## Additional Info
There is more info in issue #3780
Co-authored-by: Paul Hauner <paul@paulhauner.com>
## Proposed Changes
With proposer boosting implemented (#2822) we have an opportunity to re-org out late blocks.
This PR adds three flags to the BN to control this behaviour:
* `--disable-proposer-reorgs`: turn aggressive re-orging off (it's on by default).
* `--proposer-reorg-threshold N`: attempt to orphan blocks with less than N% of the committee vote. If this parameter isn't set then N defaults to 20% when the feature is enabled.
* `--proposer-reorg-epochs-since-finalization N`: only attempt to re-org late blocks when the number of epochs since finalization is less than or equal to N. The default is 2 epochs, meaning re-orgs will only be attempted when the chain is finalizing optimally.
For safety Lighthouse will only attempt a re-org under very specific conditions:
1. The block being proposed is 1 slot after the canonical head, and the canonical head is 1 slot after its parent. i.e. at slot `n + 1` rather than building on the block from slot `n` we build on the block from slot `n - 1`.
2. The current canonical head received less than N% of the committee vote. N should be set depending on the proposer boost fraction itself, the fraction of the network that is believed to be applying it, and the size of the largest entity that could be hoarding votes.
3. The current canonical head arrived after the attestation deadline from our perspective. This condition was only added to support suppression of forkchoiceUpdated messages, but makes intuitive sense.
4. The block is being proposed in the first 2 seconds of the slot. This gives it time to propagate and receive the proposer boost.
## Additional Info
For the initial idea and background, see: https://github.com/ethereum/consensus-specs/pull/2353#issuecomment-950238004
There is also a specification for this feature here: https://github.com/ethereum/consensus-specs/pull/3034
Co-authored-by: Michael Sproul <micsproul@gmail.com>
Co-authored-by: pawan <pawandhananjay@gmail.com>
## Issue Addressed
#3766
## Proposed Changes
Adds an endpoint to get the graffiti that will be used for the next block proposal for each validator.
## Usage
```bash
curl -H "Authorization: Bearer api-token" http://localhost:9095/lighthouse/ui/graffiti | jq
```
```json
{
"data": {
"0x81283b7a20e1ca460ebd9bbd77005d557370cabb1f9a44f530c4c4c66230f675f8df8b4c2818851aa7d77a80ca5a4a5e": "mr f was here",
"0xa3a32b0f8b4ddb83f1a0a853d81dd725dfe577d4f4c3db8ece52ce2b026eca84815c1a7e8e92a4de3d755733bf7e4a9b": "mr v was here",
"0x872c61b4a7f8510ec809e5b023f5fdda2105d024c470ddbbeca4bc74e8280af0d178d749853e8f6a841083ac1b4db98f": null
}
}
```
## Additional Info
This will only return graffiti that the validator client knows about.
That is from these 3 sources:
1. Graffiti File
2. validator_definitions.yml
3. The `--graffiti` flag on the VC
If the graffiti is set on the BN, it will not be returned. This may warrant an additional endpoint on the BN side which can be used in the event the endpoint returns `null`.
## Summary
The deposit cache now has the ability to finalize deposits. This will cause it to drop unneeded deposit logs and hashes in the deposit Merkle tree that are no longer required to construct deposit proofs. The cache is finalized whenever the latest finalized checkpoint has a new `Eth1Data` with all deposits imported.
This has three benefits:
1. Improves the speed of constructing Merkle proofs for deposits as we can just replay deposits since the last finalized checkpoint instead of all historical deposits when re-constructing the Merkle tree.
2. Significantly faster weak subjectivity sync as the deposit cache can be transferred to the newly syncing node in compressed form. The Merkle tree that stores `N` finalized deposits requires a maximum of `log2(N)` hashes. The newly syncing node then only needs to download deposits since the last finalized checkpoint to have a full tree.
3. Future proofing in preparation for [EIP-4444](https://eips.ethereum.org/EIPS/eip-4444) as execution nodes will no longer be required to store logs permanently so we won't always have all historical logs available to us.
## More Details
Image to illustrate how the deposit contract merkle tree evolves and finalizes along with the resulting `DepositTreeSnapshot`
## Other Considerations
I've changed the structure of the `SszDepositCache` so once you load & save your database from this version of lighthouse, you will no longer be able to load it from older versions.
Co-authored-by: ethDreamer <37123614+ethDreamer@users.noreply.github.com>
## Issue Addressed
Resolves#3516
## Proposed Changes
Adds a beacon fallback function for running a beacon node http query on all available fallbacks instead of returning on a first successful result. Uses the new `run_on_all` method for attestation and sync committee subscriptions.
## Additional Info
Please provide any additional information. For example, future considerations
or information useful for reviewers.
## Issue Addressed
Resolves: #3550
Remove the `--strict-fee-recipient` flag. It will cause missed proposals prior to the bellatrix transition.
Co-authored-by: realbigsean <sean@sigmaprime.io>
## Issue Addressed
[Have --checkpoint-sync-url timeout](https://github.com/sigp/lighthouse/issues/3478)
## Proposed Changes
I added a parameter for `get_bytes_opt_accept_header<U: IntoUrl>` which accept a timeout duration, and modified the body of `get_beacon_blocks_ssz` and `get_debug_beacon_states_ssz` to pass corresponding timeout durations.
## Issue Addressed
Relates to https://github.com/sigp/lighthouse/issues/3416
## Proposed Changes
- Add an `OfflineOnFailure` enum to the `first_success` method for querying beacon nodes so that a val registration request failure from the BN -> builder does not result in the BN being marked offline. This seems important because these failures could be coming directly from a connected relay and actually have no bearing on BN health. Other messages that are sent to a relay have a local fallback so shouldn't result in errors
- Downgrade the following log to a `WARN`
```
ERRO Unable to publish validator registrations to the builder network, error: All endpoints failed https://BN_B => RequestFailed(ServerMessage(ErrorMessage { code: 500, message: "UNHANDLED_ERROR: BuilderMissing", stacktraces: [] })), https://XXXX/ => Unavailable(Offline), [omitted]
```
## Additional Info
I think this change at least improves the UX of having a VC connected to some builder and some non-builder beacon nodes. I think we need to balance potentially alerting users that there is a BN <> VC misconfiguration and also allowing this type of fallback to work.
If we want to fully support this type of configuration we may want to consider adding a flag `--builder-beacon-nodes` and track whether a VC should be making builder queries on a per-beacon node basis. But I think the changes in this PR are independent of that type of extension.
PS: Sorry for the big diff here, it's mostly formatting changes after I added a new arg to a bunch of methods calls.
Co-authored-by: realbigsean <sean@sigmaprime.io>
## Issue Addressed
https://github.com/sigp/lighthouse/issues/3091
Extends https://github.com/sigp/lighthouse/pull/3062, adding pre-bellatrix block support on blinded endpoints and allowing the normal proposal flow (local payload construction) on blinded endpoints. This resulted in better fallback logic because the VC will not have to switch endpoints on failure in the BN <> Builder API, the BN can just fallback immediately and without repeating block processing that it shouldn't need to. We can also keep VC fallback from the VC<>BN API's blinded endpoint to full endpoint.
## Proposed Changes
- Pre-bellatrix blocks on blinded endpoints
- Add a new `PayloadCache` to the execution layer
- Better fallback-from-builder logic
## Todos
- [x] Remove VC transition logic
- [x] Add logic to only enable builder flow after Merge transition finalization
- [x] Tests
- [x] Fix metrics
- [x] Rustdocs
Co-authored-by: Mac L <mjladson@pm.me>
Co-authored-by: realbigsean <sean@sigmaprime.io>
## Issue Addressed
Resolves#3267Resolves#3156
## Proposed Changes
- Move the log for fee recipient checks from proposer cache insertion into block proposal so we are directly checking what we get from the EE
- Only log when there is a discrepancy with the local EE, not when using the builder API. In the `builder-api` branch there is an `info` log when there is a discrepancy, I think it is more likely there will be a difference in fee recipient with the builder api because proposer payments might be made via a transaction in the block. Not really sure what patterns will become commong.
- Upgrade the log from a `warn` to an `error` - not actually sure which we want, but I think this is worth an error because the local EE with default transaction ordering I think should pretty much always use the provided fee recipient
- add a `strict-fee-recipient` flag to the VC so we only sign blocks with matching fee recipients. Falls back from the builder API to the local API if there is a discrepancy .
Co-authored-by: realbigsean <sean@sigmaprime.io>
## Issue Addressed
Resolves#3276.
## Proposed Changes
Add a timeout for the sync committee contributions at 1/4 the slot length such that we may be able to try backup beacon nodes in the case of contribution post failure.
## Additional Info
1/4 slot length seemed standard for the timeouts, but may want to decrease this to 1/2.
I did not find any timeout related / sync committee related tests, so there are no tests. Happy to write some with a bit of guidance.
## Issue Addressed
* #3173
## Proposed Changes
Moved all `fee_recipient_file` related logic inside the `ValidatorStore` as it makes more sense to have this all together there. I tested this with the validators I have on `mainnet-shadow-fork-5` and everything appeared to work well. Only technicality is that I can't get the method to return `401` when the authorization header is not specified (it returns `400` instead). Fixing this is probably quite difficult given that none of `warp`'s rejections have code `401`.. I don't really think this matters too much though as long as it fails.
## Issue Addressed
Lays the groundwork for builder API changes by implementing the beacon-API's new `register_validator` endpoint
## Proposed Changes
- Add a routine in the VC that runs on startup (re-try until success), once per epoch or whenever `suggested_fee_recipient` is updated, signing `ValidatorRegistrationData` and sending it to the BN.
- TODO: `gas_limit` config options https://github.com/ethereum/builder-specs/issues/17
- BN only sends VC registration data to builders on demand, but VC registration data *does update* the BN's prepare proposer cache and send an updated fcU to a local EE. This is necessary for fee recipient consistency between the blinded and full block flow in the event of fallback. Having the BN only send registration data to builders on demand gives feedback directly to the VC about relay status. Also, since the BN has no ability to sign these messages anyways (so couldn't refresh them if it wanted), and validator registration is independent of the BN head, I think this approach makes sense.
- Adds upcoming consensus spec changes for this PR https://github.com/ethereum/consensus-specs/pull/2884
- I initially applied the bit mask based on a configured application domain.. but I ended up just hard coding it here instead because that's how it's spec'd in the builder repo.
- Should application mask appear in the api?
Co-authored-by: realbigsean <sean@sigmaprime.io>
## Issue Addressed
#3154
## Proposed Changes
Add three new metrics for the VC:
1. `vc_beacon_nodes_synced_count`
2. `vc_beacon_nodes_available_count`
3. `vc_beacon_nodes_total_count`
Their values mirror the values present in the following log line:
```
Apr 08 17:25:17.000 INFO Connected to beacon node(s) synced: 4, available: 4, total: 4, service: notifier
```
# Description
Since the `TaskExecutor` currently requires a `Weak<Runtime>`, it's impossible to use it in an async test where the `Runtime` is created outside our scope. Whilst we *could* create a new `Runtime` instance inside the async test, dropping that `Runtime` would cause a panic (you can't drop a `Runtime` in an async context).
To address this issue, this PR creates the `enum Handle`, which supports either:
- A `Weak<Runtime>` (for use in our production code)
- A `Handle` to a runtime (for use in testing)
In theory, there should be no change to the behaviour of our production code (beyond some slightly different descriptions in HTTP 500 errors), or even our tests. If there is no change, you might ask *"why bother?"*. There are two PRs (#3070 and #3175) that are waiting on these fixes to introduce some new tests. Since we've added the EL to the `BeaconChain` (for the merge), we are now doing more async stuff in tests.
I've also added a `RuntimeExecutor` to the `BeaconChainTestHarness`. Whilst that's not immediately useful, it will become useful in the near future with all the new async testing.
## Issue Addressed
MEV boost compatibility
## Proposed Changes
See #2987
## Additional Info
This is blocked on the stabilization of a couple specs, [here](https://github.com/ethereum/beacon-APIs/pull/194) and [here](https://github.com/flashbots/mev-boost/pull/20).
Additional TODO's and outstanding questions
- [ ] MEV boost JWT Auth
- [ ] Will `builder_proposeBlindedBlock` return the revealed payload for the BN to propogate
- [ ] Should we remove `private-tx-proposals` flag and communicate BN <> VC with blinded blocks by default once these endpoints enter the beacon-API's repo? This simplifies merge transition logic.
Co-authored-by: realbigsean <seananderson33@gmail.com>
Co-authored-by: realbigsean <sean@sigmaprime.io>
## Issue Addressed
#2883
## Proposed Changes
* Added `suggested-fee-recipient` & `suggested-fee-recipient-file` flags to validator client (similar to graffiti / graffiti-file implementation).
* Added proposer preparation service to VC, which sends the fee-recipient of all known validators to the BN via [/eth/v1/validator/prepare_beacon_proposer](https://github.com/ethereum/beacon-APIs/pull/178) api once per slot
* Added [/eth/v1/validator/prepare_beacon_proposer](https://github.com/ethereum/beacon-APIs/pull/178) api endpoint and preparation data caching
* Added cleanup routine to remove cached proposer preparations when not updated for 2 epochs
## Additional Info
Changed the Implementation following the discussion in #2883.
Co-authored-by: pk910 <philipp@pk910.de>
Co-authored-by: Paul Hauner <paul@paulhauner.com>
Co-authored-by: Philipp K <philipp@pk910.de>
