Seems solved, Not reproducible on VyOS 1.4-rolling-202201180317

PR: https://github.com/vyos/vyos-1x/pull/1139

To reproduce it should be zone-policy firewall rules, for example:

The correct key for sflow sfprobe_source_ip
PR https://github.com/vyos/vyos-1x/pull/1099

The ISC DHCP relay in VyOS is completely broken for my (non-GRE) use case, I would really like to see it get tossed out for something that works. This might not be the best place to describe my relay problems, but I might as well (skip this paragraph it you're not interested). My setup basically consists of the (ISC) DHCP server host connected to the VyOS router (running on a Dell R320), directly connected to a Cisco ASR920 router. Both VyOS and the ASR are directly connected to user VLANs (VyOS for firewalled/NATed zones and ASR for high-traffic users) and have DHCP relays set up targeting the DHCP server, such that the relayed messages from the ASR passes through the VyOS router towards the DHCP server and should get routed normally (i.e. ignored by the VyOS relay). The VyOS DHCP relay doesn't like this and starts spamming the DHCP messages up to ten or more times, causing wired clients to have to wait maybe ten seconds before getting an IPv4 address and wireless clients to just time out and abort the connection. I can provide the relay logs (mainly screenshots unless i dig up the disk I used) and VyOS config if anyone wants them, but as they have sensitive addresses, I don't intend to post them publicly. EDIT: I should mention that I didn't notice any problems while testing it with only myself, it was when 200 people started connecting the problems started occurring. And the DHCP server VM was not showing any noticable load.

If this package supports all existing setups and the GRE usecase I see no reason to not replace it. @basalblas PR is happily accepted.

Keep in mind you cannot run dhcp-helper and ISC DHCP server at the same time on a single router. The Vyos CLI should not allow this.

Fixed

set nat source rule 1000 outbound-interface 'eth1'
set nat source rule 1000 source address '203.0.113.1-203.0.113.4'
set nat source rule 1000 translation address '10.0.0.1-10.0.0.4'
[email protected]# commit
[ nat ]
Warning: IP address 10.0.0.1 does not exist on the system!
Warning: IP address 10.0.0.4 does not exist on the system!

duplicate of T2468

Thank you for reporting this issue, it looks like that parser allows ranges of IP address (IP hyphen IP) but the parser does not. You could get around using CIDR notation but this indeed need looking into.

By the way, may I say there are several bugs of stop function in vyos-router?

Why not use WantedBy instead of RequiredBy in vyos-hostsd.service like:

My original thoughts was quite straight forward, modify /usr/libexec/vyos/init/vyos-router as below:

Hello, @MapleWang!
Unfortunately, I cannot find any other reliable way to configure vyos-hostsd service to be running before the vyos-router. In fact, vyos-hostsd is really necessary to be running for proper work of the VyOS system, so we can consider this even from the other point of view - how to keep all services operable after the vyos-router restart?
If you will have any ideas, which can help to decrease the overall impact of this situation, we would be happy to get them.

Really thanks for your reply. It's nice to have this fix. But to be honest, crash of vyos-hostsd is not so big deal for me, what really concern me is that restart of vyos-hostsd is followed by restart of vyos-router.

Hello, @MapleWang!
Thank you for pointing our attention to this issue! It is really bad that such simple action as changing hostname in some cases (well, in fact not only this but it is easy to reproduce) leads to the whole router crash.
The problem consists of several parts:

1. In old systemd versions (which is used in Debian Jessie and VyOS 1.2) exists a problem, when during a restart of systemd-journald all pipes between this daemon and systemd services are disconnecting.
2. In vyos-hostsd, which is responsible for hostname and DNS and controlled by systemd we used print() for logging and debug purposed without enough handling of errors.

So, when arises the situation when there is no PIPE connection between vyos-hostsd and systemd-journald, vyos-hostsd not able to print messages and crashes. :(

I found a easy way to reproduce.