PyLink Relay (aka "Relay") provides transparent server-side relaying between channels, letting networks share channels on demand without going through all the fuss of a hard link. Each network retains its own opers and services, with default behaviour being so that oper features (kill, overrides, etc.) are isolated to only work on channels they own. If you're familiar with Janus, you can think of PyLink Relay as being a rewrite of it from scratch (though PyLink can do much more via its other plugins!).
This guide goes over some of the basic commands in Relay, as well as all the must-know notes.
The default Relay configuration in will automatically tag users from other networks with a suffix such as `/net`. The purpose of this is to prevent confusing nick collisions if the same nick is used on multiple linked networks, and ensure that remote networks' nicks effectively use their own namespace.
How is this relevant to an operator? Firstly, it means that you **cannot ban users** using banmasks such as `*/net1!*@*`! The nick suffix is something PyLink adds artificially; on `net1`'s IRCd, which check the bans locally, the nick suffix doesn't exist and will therefore *not* match anyone.
## Services compatibility
While PyLink is generally able to run independently of individual networks's services, there are some gotchas. This list briefly details services features that have been known to cause problems with Relay. **Using any of these features in conjunction with Relay is *not* supported.**
- Rationale: it is common for a person to want to connect to multiple networks in a Relay instance, because they are still independent entities. You can still use IRCd-side clones prevention, which sanely blocks connections instead of killing / banning everyone involved.
- Atheme: **The ChanFix service should be disabled**
- Rationale: ChanFix is incompatible with Relay CLAIM because it overrides ops on relay channels whenever they appear "opless". This basic op check is unable to consider the case of remote channel services not being set to join channels, and will instead cause join/message/part spam as CLAIM reverts the ChanFix service's mode changes.
- Rationale: This will just make PyLink split off - you should instead [delink any problem networks / channels](#dealing-with-disputes-and-emergencies).
- Not following these rules means that it's very easy for the Relay instances to go in a loop should an operator run the wrong command, which will hammer your CPU and relentlessly spam your channels.
Channel claims are a feature which prevents oper override (MODE, KICK, TOPIC, KILL, OJOIN, ...) from working on channels not owned by or whitelisting a network. By default, CLAIM is enabled for all new channels, though this can be configured in PyLink 2.0+ via the [`relay::enable_default_claim` option](https://github.com/jlu5/PyLink/blob/2.0-beta1/example-conf.yml#L771-L774). Unless the claimed network list of a channel is EMPTY, oper override will only be allowed from networks on that list.
To set a claim (note: for these commands, you must be on the network which created the channel in question!):
-`/msg PyLink claim #channel yournet,net2,net3` (the last parameter is a case-sensitive comma-separated list of networks)
To list claim networks on a channel:
-`/msg PyLink claim #channel`
To clear the claim list for a channel:
-`/msg PyLink claim #channel -`
### Access control for links (LINKACL)
LINKACL allows you to blacklist or whitelist networks from linking to your channel. The default configuration enables blacklist mode by default, though this can be configured via the [`relay::linkacl_use_whitelist` option](https://github.com/jlu5/PyLink/blob/2.0-beta1/example-conf.yml#L766-L769).
- Note that when you switch between LINKACL modes, the LINKACL entries from the previous mode are stored and stashed away. This means that you will get an empty LINKACL list in the new LINKACL mode if you haven't used it already, and that you can reload the previous LINKACL mode's entries by switching back to it at any point.
-`/msg PyLink chandesc #channel your text goes here`
To remove the description for a channel:
-`/msg PyLink chandesc #channel -`
## Dealing with disputes and emergencies
The best thing to do in the event of a dispute is to delink the problem networks / channels. KILLs and network bans (K/G/ZLINE) will most often *not* behave the way you expect it to.
1) If the sender was a server and not a client, reject the kill.
2) If the target and source networks are both in a(ny) [kill share pool](https://github.com/jlu5/PyLink/blob/2.0-beta1/example-conf.yml#L725-L735), relay the kill as-is.
3) Otherwise, check every channels the kill target is in:
- If the killer has claim access in a channel, forward the KILL as a kick to that channel.
- Otherwise, bounce the kill silently.
### Network bans (K/G/ZLINE)
Network bans are purposely not supported; see https://github.com/jlu5/PyLink/issues/521#issuecomment-352316396.
### Delinking channels
To delink another network from a channel your network owns:
-`/msg PyLink delink #yourchannel badnetwork`
To delink your network from a bad network's channel:
-`/msg PyLink delink #badchannel`
Basically, only one of the two above commands will work for one specific channel. Almost always, the network that owns a channel should be the one who has it registered via their services. You can see a list of channels by typing `/msg PyLink linked`.
