townforge/README.md
2021-06-03 10:39:38 +00:00

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# Townforge
Copyright (c) 2019-2021 Crypto City
Copyright (c) 2014-2021 The Monero Project.
Portions Copyright (c) 2012-2013 The Cryptonote developers.
## Table of Contents
- [Development resources](#development-resources)
- [Vulnerability response](#vulnerability-response)
- [Introduction](#introduction)
- [License](#license)
- [Contributing](#contributing)
- [Compiling Townforge from source](#compiling-townforge-from-source)
- [Dependencies](#dependencies)
- [Internationalization](#Internationalization)
- [Using Tor](#using-tor)
- [Pruning](#Pruning)
- [Debugging](#Debugging)
- [Merge mining](#merge-mining)
- [Known issues](#known-issues)
## Development resources
- Web: [www.townforge.net](https://www.townforge.net)
- GitHub: [https://git.townforge.net/townforge/townforge](https://git.townforge.net/townforge/townforge)
- Forum: [forum.townforge.net](https://forum.townforge.net)
- IRC: [##townforge on Freenode](https://webchat.freenode.net/?randomnick=1&channels=%23%23townforge&prompt=1&uio=d4)
## Vulnerability response
- If in Monero, refer to the Monero [Vulnerability Response Process](https://github.com/monero-project/meta/blob/master/VULNERABILITY_RESPONSE_PROCESS.md)
- Otherwise, contact moneromooo on Freenode IRC.
## Introduction
Townforge is a blockchain based game based on the Monero source. Buy land, create buildings and research new technologies.
## License
See [LICENSE](LICENSE).
## Contributing
If you want to help out, see [CONTRIBUTING](docs/CONTRIBUTING.md) for a set of guidelines.
## Compiling Townforge from source
### Dependencies
The following table summarizes the tools and libraries required to build. A
few of the libraries are also included in this repository (marked as
"Vendored"). By default, the build uses the library installed on the system
and ignores the vendored sources. However, if no library is found installed on
the system, then the vendored source will be built and used. The vendored
sources are also used for statically-linked builds because distribution
packages often include only shared library binaries (`.so`) but not static
library archives (`.a`).
| Dep | Min. version | Vendored | Debian/Ubuntu pkg | Arch pkg | Void pkg | Fedora pkg | Optional | Purpose |
| ------------ | ------------- | -------- | -------------------- | ------------ | ------------------ | ------------------- | -------- | --------------- |
| GCC | 4.7.3 | NO | `build-essential` | `base-devel` | `base-devel` | `gcc` | NO | |
| CMake | 3.5 | NO | `cmake` | `cmake` | `cmake` | `cmake` | NO | |
| pkg-config | any | NO | `pkg-config` | `base-devel` | `base-devel` | `pkgconf` | NO | |
| OpenSSL | basically any | NO | `libssl-dev` | `openssl` | `libressl-devel` | `openssl-devel` | NO | sha256 sum |
| libzmq | 4.2.0 | NO | `libzmq3-dev` | `zeromq` | `zeromq-devel` | `zeromq-devel` | NO | ZeroMQ library |
| OpenPGM | ? | NO | `libpgm-dev` | `libpgm` | | `openpgm-devel` | NO | For ZeroMQ |
| libnorm[2] | ? | NO | `libnorm-dev` | | | | YES | For ZeroMQ |
| libunbound | 1.4.16 | YES | `libunbound-dev` | `unbound` | `unbound-devel` | `unbound-devel` | NO | DNS resolver |
| libsodium | ? | NO | `libsodium-dev` | `libsodium` | `libsodium-devel` | `libsodium-devel` | NO | cryptography |
| libunwind | any | NO | `libunwind8-dev` | `libunwind` | `libunwind-devel` | `libunwind-devel` | YES | Stack traces |
| liblzma | any | NO | `liblzma-dev` | `xz` | `liblzma-devel` | `xz-devel` | YES | For libunwind |
| libreadline | 6.3.0 | NO | `libreadline6-dev` | `readline` | `readline-devel` | `readline-devel` | YES | Input editing |
| ldns | 1.6.17 | NO | `libldns-dev` | `ldns` | `libldns-devel` | `ldns-devel` | YES | SSL toolkit |
| expat | 1.1 | NO | `libexpat1-dev` | `expat` | `expat-devel` | `expat-devel` | YES | XML parsing |
| GTest | 1.5 | YES | `libgtest-dev`[1] | `gtest` | `gtest-devel` | `gtest-devel` | YES | Test suite |
| ccache | any | NO | `ccache` | `ccache` | `ccache` | `ccache` | YES | Compil. cache |
| Doxygen | any | NO | `doxygen` | `doxygen` | `doxygen` | `doxygen` | YES | Documentation |
| Graphviz | any | NO | `graphviz` | `graphviz` | `graphviz` | `graphviz` | YES | Documentation |
| lrelease | ? | NO | `qttools5-dev-tools` | `qt5-tools` | `qt5-tools` | `qt5-linguist` | YES | Translations |
| libhidapi | ? | NO | `libhidapi-dev` | `hidapi` | `hidapi-devel` | `hidapi-devel` | YES | Hardware wallet |
| libusb | ? | NO | `libusb-1.0-0-dev` | `libusb` | `libusb-devel` | `libusbx-devel` | YES | Hardware wallet |
| libprotobuf | ? | NO | `libprotobuf-dev` | `protobuf` | `protobuf-devel` | `protobuf-devel` | YES | Hardware wallet |
| protoc | ? | NO | `protobuf-compiler` | `protobuf` | `protobuf` | `protobuf-compiler` | YES | Hardware wallet |
| libudev | ? | No | `libudev-dev` | `systemd` | `eudev-libudev-devel` | `systemd-devel` | YES | Hardware wallet |
| OpenGL[3] | ? | NO | | | | | NO | Graphics API |
| libudev | ? | No | `libudev-dev` | `systemd` | `eudev-libudev-devel` | `systemd-devel` | YES | Hardware wallet |
| flex | ? | No | | | | `flex` | NO | Script language |
| bison | ? | No | | | | `bison` | NO | Script language |
[1] On Debian/Ubuntu `libgtest-dev` only includes sources and headers. You must
build the library binary manually. This can be done with the following command ```sudo apt-get install libgtest-dev && cd /usr/src/gtest && sudo cmake . && sudo make && sudo mv libg* /usr/lib/ ```
[2] libnorm-dev is needed if your zmq library was built with libnorm, and not needed otherwise
[3] An OpenGL implementation may be available from your graphics card vendor, or a software implementation exists: MESA
Install all dependencies at once on Debian/Ubuntu:
``` sudo apt update && sudo apt install build-essential cmake pkg-config libssl-dev libzmq3-dev libunbound-dev libsodium-dev libunwind8-dev liblzma-dev libreadline6-dev libldns-dev libexpat1-dev libpgm-dev qttools5-dev-tools libhidapi-dev libusb-1.0-0-dev libprotobuf-dev protobuf-compiler libudev-dev libboost-chrono-dev libboost-date-time-dev libboost-filesystem-dev libboost-locale-dev libboost-program-options-dev libboost-regex-dev libboost-serialization-dev libboost-system-dev libboost-thread-dev ccache doxygen graphviz libxinerama-dev libxrender-dev libxext-dev libgl1-mesa-dev xinput ```
Install all dependencies at once on macOS with the provided Brewfile:
``` brew update && brew bundle --file=contrib/brew/Brewfile ```
FreeBSD 12.1 one-liner required to build dependencies:
```pkg install git gmake cmake pkgconf boost-libs libzmq4 libsodium```
### Cloning the repository
Clone recursively to pull-in needed submodule(s):
`$ git clone --recursive https://git.townforge.net/townforge/townforge`
If you already have a repo cloned, initialize and update:
`$ cd townforge && git submodule init && git submodule update`
*Note*: If there are submodule differences between branches, you may need
to use ```git submodule sync && git submodule update``` after changing branches
to build successfully.
### Build instructions
Townforge uses the CMake build system and a top-level [Makefile](Makefile) that
invokes cmake commands as needed.
#### On Linux and macOS
* Install the dependencies
* Change to the root of the source code directory, change to the most recent release branch, and build:
```bash
cd townforge
git checkout v0.31.0.0
make
```
*Optional*: If your machine has several cores and enough memory, enable
parallel build by running `make -j<number of threads>` instead of `make`. For
this to be worthwhile, the machine should have one core and about 2GB of RAM
available per thread.
*Note*: The instructions above will compile the most stable release of the
Townforge software. If you would like to use and test the most recent software,
use ```git checkout master```. The master branch may contain updates that are
both unstable and incompatible with release software, though testing is always
encouraged.
* The resulting executables can be found in `build/release/bin`
* Add `PATH="$PATH:$HOME/townforge/build/release/bin"` to `.profile`
* Run the Townforge daemon with `townforged --detach`
* **Optional**: build and run the test suite to verify the binaries:
```bash
make release-test
```
*NOTE*: `core_tests` test may take a few hours to complete.
* **Optional**: to build binaries suitable for debugging:
```bash
make debug
```
* **Optional**: to build statically-linked binaries:
```bash
make release-static
```
Dependencies need to be built with -fPIC. Static libraries usually aren't, so you may have to build them yourself with -fPIC. Refer to their documentation for how to build them.
* **Optional**: build documentation in `doc/html` (omit `HAVE_DOT=YES` if `graphviz` is not installed):
```bash
HAVE_DOT=YES doxygen Doxyfile
```
#### On Windows:
Binaries for Windows are built on Windows using the MinGW toolchain within
[MSYS2 environment](https://www.msys2.org). The MSYS2 environment emulates a
POSIX system. The toolchain runs within the environment and *cross-compiles*
binaries that can run outside of the environment as a regular Windows
application.
**Preparing the build environment**
* Download and install the [MSYS2 installer](https://www.msys2.org), either the 64-bit or the 32-bit package, depending on your system.
* Open the MSYS shell via the `MSYS2 Shell` shortcut
* Update packages using pacman:
```bash
pacman -Syu
```
* Exit the MSYS shell using Alt+F4
* Edit the properties for the `MSYS2 Shell` shortcut changing "msys2_shell.bat" to "msys2_shell.cmd -mingw64" for 64-bit builds or "msys2_shell.cmd -mingw32" for 32-bit builds
* Restart MSYS shell via modified shortcut and update packages again using pacman:
```bash
pacman -Syu
```
* Install dependencies:
To build for 64-bit Windows:
```bash
pacman -S mingw-w64-x86_64-toolchain make mingw-w64-x86_64-cmake mingw-w64-x86_64-boost mingw-w64-x86_64-openssl mingw-w64-x86_64-zeromq mingw-w64-x86_64-libsodium mingw-w64-x86_64-hidapi
```
To build for 32-bit Windows:
```bash
pacman -S mingw-w64-i686-toolchain make mingw-w64-i686-cmake mingw-w64-i686-boost mingw-w64-i686-openssl mingw-w64-i686-zeromq mingw-w64-i686-libsodium mingw-w64-i686-hidapi
```
* Open the MingW shell via `MinGW-w64-Win64 Shell` shortcut on 64-bit Windows
or `MinGW-w64-Win64 Shell` shortcut on 32-bit Windows. Note that if you are
running 64-bit Windows, you will have both 64-bit and 32-bit MinGW shells.
**Cloning**
* To git clone, run:
```bash
git clone --recursive https://git.townforge.net/townforge/townforge
```
**Building**
* Change to the cloned directory, run:
```bash
cd townforge
```
* If you would like a specific version/tag, do a git checkout for that version. eg. 'v0.31.0.0'. If you don't care about the version and just want binaries from master, skip this step:
```bash
git checkout v0.31.0.0
```
* If you are on a 64-bit system, run:
```bash
make release-static-win64
```
* If you are on a 32-bit system, run:
```bash
make release-static-win32
```
* The resulting executables can be found in `build/release/bin`
* **Optional**: to build Windows binaries suitable for debugging on a 64-bit system, run:
```bash
make debug-static-win64
```
* **Optional**: to build Windows binaries suitable for debugging on a 32-bit system, run:
```bash
make debug-static-win32
```
* The resulting executables can be found in `build/debug/bin`
### On FreeBSD:
The project can be built from scratch by following instructions for Linux above(but use `gmake` instead of `make`).
If you are running Townforge in a jail you need to add `sysvmem="new"` to your jail configuration, otherwise lmdb will throw the error message: `Failed to open lmdb environment: Function not implemented`.
### On OpenBSD:
You will need to add a few packages to your system. `pkg_add cmake gmake zeromq libiconv boost`.
The `doxygen` and `graphviz` packages are optional and require the xbase set.
Running the test suite also requires `py-requests` package.
Build townforge: `env DEVELOPER_LOCAL_TOOLS=1 BOOST_ROOT=/usr/local gmake release-static`
Note: you may encounter the following error, when compiling the latest version of Townforge as a normal user:
```
LLVM ERROR: out of memory
c++: error: unable to execute command: Abort trap (core dumped)
```
Then you need to increase the data ulimit size to 2GB and try again: `ulimit -d 2000000`
### On NetBSD:
Check that the dependencies are present: `pkg_info -c libexecinfo boost-headers boost-libs protobuf readline libusb1 zeromq git-base pkgconf gmake cmake | more`, and install any that are reported missing, using `pkg_add` or from your pkgsrc tree. Readline is optional but worth having.
Third-party dependencies are usually under `/usr/pkg/`, but if you have a custom setup, adjust the "/usr/pkg" (below) accordingly.
Clone the monero repository recursively and checkout the most recent release as described above. Then build monero: `gmake BOOST_ROOT=/usr/pkg LDFLAGS="-Wl,-R/usr/pkg/lib" release`. The resulting executables can be found in `build/NetBSD/[Release version]/Release/bin/`.
### On Solaris:
The default Solaris linker can't be used, you have to install GNU ld, then run cmake manually with the path to your copy of GNU ld:
```bash
mkdir -p build/release
cd build/release
cmake -DCMAKE_LINKER=/path/to/ld -D CMAKE_BUILD_TYPE=Release ../..
cd ../..
```
Then you can run make as usual.
### On Linux for Android (using docker):
```bash
# Build image (for ARM 32-bit)
docker build -f utils/build_scripts/android32.Dockerfile -t townforge-android .
# Build image (for ARM 64-bit)
docker build -f utils/build_scripts/android64.Dockerfile -t townforge-android .
# Create container
docker create -it --name townforge-android townforge-android bash
# Get binaries
docker cp townforge-android:/src/build/release/bin .
```
### Building portable statically linked binaries
By default, in either dynamically or statically linked builds, binaries target the specific host processor on which the build happens and are not portable to other processors. Portable binaries can be built using the following targets:
* ```make release-static-linux-x86_64``` builds binaries on Linux on x86_64 portable across POSIX systems on x86_64 processors
* ```make release-static-linux-i686``` builds binaries on Linux on x86_64 or i686 portable across POSIX systems on i686 processors
* ```make release-static-linux-armv8``` builds binaries on Linux portable across POSIX systems on armv8 processors
* ```make release-static-linux-armv7``` builds binaries on Linux portable across POSIX systems on armv7 processors
* ```make release-static-linux-armv6``` builds binaries on Linux portable across POSIX systems on armv6 processors
* ```make release-static-win64``` builds binaries on 64-bit Windows portable across 64-bit Windows systems
* ```make release-static-win32``` builds binaries on 64-bit or 32-bit Windows portable across 32-bit Windows systems
### Cross Compiling
You can also cross-compile static binaries on Linux for Windows and macOS with the `depends` system.
* ```make depends target=x86_64-linux-gnu``` for 64-bit linux binaries.
* ```make depends target=x86_64-w64-mingw32``` for 64-bit windows binaries.
* Requires: `python3 g++-mingw-w64-x86-64 wine1.6 bc`
* ```make depends target=x86_64-apple-darwin11``` for macOS binaries.
* Requires: `cmake imagemagick libcap-dev librsvg2-bin libz-dev libbz2-dev libtiff-tools python-dev`
* ```make depends target=i686-linux-gnu``` for 32-bit linux binaries.
* Requires: `g++-multilib bc`
* ```make depends target=i686-w64-mingw32``` for 32-bit windows binaries.
* Requires: `python3 g++-mingw-w64-i686`
* ```make depends target=arm-linux-gnueabihf``` for armv7 binaries.
* Requires: `g++-arm-linux-gnueabihf`
* ```make depends target=aarch64-linux-gnu``` for armv8 binaries.
* Requires: `g++-aarch64-linux-gnu`
* ```make depends target=riscv64-linux-gnu``` for RISC V 64 bit binaries.
* Requires: `g++-riscv64-linux-gnu`
* ```make depends target=x86_64-unknown-freebsd``` for freebsd binaries.
* Requires: `clang-8`
* ```make depends target=arm-linux-android``` for 32bit android binaries
* ```make depends target=aarch64-linux-android``` for 64bit android binaries
The required packages are the names for each toolchain on apt. Depending on your distro, they may have different names.
Using `depends` might also be easier to compile Townforge on Windows than using MSYS. Activate Windows Subsystem for Linux (WSL) with a distro (for example Ubuntu), install the apt build-essentials and follow the `depends` steps as depicted above.
The produced binaries still link libc dynamically. If the binary is compiled on a current distribution, it might not run on an older distribution with an older installation of libc. Passing `-DBACKCOMPAT=ON` to cmake will make sure that the binary will run on systems having at least libc version 2.17.
## Running townforged
The build places the binary in `bin/` sub-directory within the build directory
from which cmake was invoked (repository root by default). To run in the
foreground:
```bash
./bin/townforged
```
To list all available options, run `./bin/townforged --help`. Options can be
specified either on the command line or in a configuration file passed by the
`--config-file` argument. To specify an option in the configuration file, add
a line with the syntax `argumentname=value`, where `argumentname` is the name
of the argument without the leading dashes, for example, `log-level=1`.
To run in background:
```bash
./bin/townforged --log-file townforged.log --detach
```
To run as a systemd service, copy
[townforged.service](utils/systemd/townforged.service) to `/etc/systemd/system/` and
[townforged.conf](utils/conf/townforged.conf) to `/etc/`. The [example
service](utils/systemd/townforged.service) assumes that the user `townforge` exists
and its home is the data directory specified in the [example
config](utils/conf/townforged.conf).
If you're on Mac, you may need to add the `--max-concurrency 1` option to
townforge-wallet-cli, and possibly townforged, if you get crashes refreshing.
# running the game
```bash
./bin/townforge
```
## Internationalization
See [README.i18n.md](docs/README.i18n.md).
## Using Tor
> There is a new, still experimental, [integration with Tor](docs/ANONYMITY_NETWORKS.md). The
> feature allows connecting over IPv4 and Tor simultaneously - IPv4 is used for
> relaying blocks and relaying transactions received by peers whereas Tor is
> used solely for relaying transactions received over local RPC. This provides
> privacy and better protection against surrounding node (sybil) attacks.
While Townforge isn't made to integrate with Tor, it can be used wrapped with torsocks, by
setting the following configuration parameters and environment variables:
* `--p2p-bind-ip 127.0.0.1` on the command line or `p2p-bind-ip=127.0.0.1` in
townforged.conf to disable listening for connections on external interfaces.
* `--no-igd` on the command line or `no-igd=1` in townforged.conf to disable IGD
(UPnP port forwarding negotiation), which is pointless with Tor.
* `DNS_PUBLIC=tcp` or `DNS_PUBLIC=tcp://x.x.x.x` where x.x.x.x is the IP of the
desired DNS server, for DNS requests to go over TCP, so that they are routed
through Tor. When IP is not specified, townforged uses the default list of
servers defined in [src/common/dns_utils.cpp](src/common/dns_utils.cpp).
* `TORSOCKS_ALLOW_INBOUND=1` to tell torsocks to allow townforged to bind to interfaces
to accept connections from the wallet. On some Linux systems, torsocks
allows binding to localhost by default, so setting this variable is only
necessary to allow binding to local LAN/VPN interfaces to allow wallets to
connect from remote hosts. On other systems, it may be needed for local wallets
as well.
* Do NOT pass `--detach` when running through torsocks with systemd, (see
[utils/systemd/townforged.service](utils/systemd/townforged.service) for details).
* If you use the wallet with a Tor daemon via the loopback IP (eg, 127.0.0.1:9050),
then use `--untrusted-daemon` unless it is your own hidden service.
Example command line to start townforged through Tor:
```bash
DNS_PUBLIC=tcp torsocks townforged --p2p-bind-ip 127.0.0.1 --no-igd
```
A helper script is in contrib/tor/monero-over-tor.sh. It assumes Tor is installed
already, and runs Tor and Monero with the right configuration.
### Using Tor on Tails
TAILS ships with a very restrictive set of firewall rules. Therefore, you need
to add a rule to allow this connection too, in addition to telling torsocks to
allow inbound connections. Full example:
```bash
sudo iptables -I OUTPUT 2 -p tcp -d 127.0.0.1 -m tcp --dport 18881 -j ACCEPT
DNS_PUBLIC=tcp torsocks ./townforged --p2p-bind-ip 127.0.0.1 --no-igd --rpc-bind-ip 127.0.0.1 \
--data-dir /home/amnesia/Persistent/your/directory/to/the/blockchain
```
## Pruning
As of May 2020, the full Monero blockchain file is about 100 GB. One can store a pruned blockchain, which is about 30 GB.
A pruned blockchain can only serve part of the historical chain data to other peers, but is otherwise identical in
functionality to the full blockchain.
To use a pruned blockchain, it is best to start the initial sync with `--prune-blockchain`. However, it is also possible
to prune an existing blockchain using the `monero-blockchain-prune` tool or using the `--prune-blockchain` `monerod` option
with an existing chain. If an existing chain exists, pruning will temporarily require disk space to store both the full
and pruned blockchains.
For more detailed information see the ['Pruning' entry in the Moneropedia](https://www.getmonero.org/resources/moneropedia/pruning.html)
## Debugging
This section contains general instructions for debugging failed installs or problems encountered with Townforge. First, ensure you are running the latest version built from the git repo.
### Obtaining stack traces and core dumps on Unix systems
We generally use the tool `gdb` (GNU debugger) to provide stack trace functionality, and `ulimit` to provide core dumps in builds which crash or segfault.
* To use `gdb` in order to obtain a stack trace for a build that has stalled:
Run the build.
Once it stalls, enter the following command:
```bash
gdb /path/to/townforged `pidof townforged`
```
Type `thread apply all bt` within gdb in order to obtain the stack trace
* If however the core dumps or segfaults:
Enter `ulimit -c unlimited` on the command line to enable unlimited filesizes for core dumps
Enter `echo core | sudo tee /proc/sys/kernel/core_pattern` to stop cores from being hijacked by other tools
Run the build.
When it terminates with an output along the lines of "Segmentation fault (core dumped)", there should be a core dump file in the same directory as townforged. It may be named just `core`, or `core.xxxx` with numbers appended.
You can now analyse this core dump with `gdb` as follows:
```bash
gdb /path/to/townforged /path/to/dumpfile`
```
Print the stack trace with `bt`
* If a program crashed and cores are managed by systemd, the following can also get a stack trace for that crash:
```bash
coredumpctl -1 gdb
```
#### To run Townforge within gdb:
Type `gdb /path/to/townforged`
Pass command-line options with `--args` followed by the relevant arguments
Type `run` to run townforged
### Analysing memory corruption
There are two tools available:
#### ASAN
Configure Townforge with the -D SANITIZE=ON cmake flag, eg:
```bash
cd build/debug && cmake -D SANITIZE=ON -D CMAKE_BUILD_TYPE=Debug ../..
```
You can then run the townforge tools normally. Performance will typically halve.
#### valgrind
Install valgrind and run as `valgrind /path/to/townforged`. It will be very slow.
### LMDB
Instructions for debugging suspected blockchain corruption as per @HYC
There is an `mdb_stat` command in the LMDB source that can print statistics about the database but it's not routinely built. This can be built with the following command:
```bash
cd ~/townforge/external/db_drivers/liblmdb && make
```
The output of `mdb_stat -ea <path to blockchain dir>` will indicate inconsistencies in the blocks, block_heights and block_info table.
The output of `mdb_dump -s blocks <path to blockchain dir>` and `mdb_dump -s block_info <path to blockchain dir>` is useful for indicating whether blocks and block_info contain the same keys.
These records are dumped as hex data, where the first line is the key and the second line is the data.
# Merge mining
Townforge can be merge mined with Monero.
Merge mining is a way to mine two blockchains with the same proof of work algorithm at the same time without using extra hash power.
It benefits both chains, since each ends up protected by the work done for the other as well as the work done for itself.
Merge mining Townforge is very simple, thanks to a proxy server (townforge-merge-mining-proxy) which does all the nitty gritty transparently:
this proxy acts like a Monero daemon, proxying RPC to the real Monero daemon, and also connects to a Townforge daemon so it can update the
Monero block templates to allow merge mining. The downstream miner does not need to know about the changes and can mine as usual.
Consider a setup where xmrig is being used to mine Monero:
```
monerod --rpc-bind-port 18081
xmrig --coin monero --url 127.0.0.1:18081 --daemon --user 4....
```
Merge mining needs the Townforge daemon to run, and the Townforge merge mining proxy to connect both daemons. xmrig can then mine to the proxy:
```
monerod --rpc-bind-port 18083
townforged --rpc-bind-port 18881
townforge-merge-mining-proxy --rpc-bind-port 18081 --monero-daemon-address 127.0.0.1:18083 --aux-daemon-address 127.0.0.1:18881 --aux-wallet-address TF1....
xmrig --coin monero --url 127.0.0.1:18081 --daemon --user 4....
```
Here, xmrig will talk to the proxy, which is configured to merge mining Townforge to the address TF1.... Note how the xmrig command line
did not change.
# Known Issues
## Protocols
### Socket-based
Because of the nature of the socket-based protocols that drive townforge, certain protocol weaknesses are somewhat unavoidable at this time. While these weaknesses can theoretically be fully mitigated, the effort required (the means) may not justify the ends. As such, please consider taking the following precautions if you are a townforge node operator:
- Run `townforged` on a "secured" machine. If operational security is not your forte, at a very minimum, have a dedicated a computer running `townforged` and **do not** browse the web, use email clients, or use any other potentially harmful apps on your `townforged` machine. **Do not click links or load URL/MUA content on the same machine**. Doing so may potentially exploit weaknesses in commands which accept "localhost" and "127.0.0.1".
- If you plan on hosting a public "remote" node, start `townforged` with `--restricted-rpc`. This is a must.
### Blockchain-based
Certain blockchain "features" can be considered "bugs" if misused correctly. Consequently, please consider the following:
- When receiving monero currency, be aware that it may be locked for an arbitrary time if the sender elected to, preventing you from spending that currency until the lock time expires. You may want to hold off acting upon such a transaction until the unlock time lapses. To get a sense of that time, you can consider the remaining blocktime until unlock as seen in the `show_transfers` command.