Caddy v1 Broken with Docker v20.10.0

[joesixpack]

The latest Docker v20.10.0 update appears to have broken Caddy which is also very old and outdated at v1.

`goroutine 1 [running]:
github.com/mholt/caddy/vendor/github.com/miekg/dns.ClientConfigFromFile(0xbb4739, 0x10, 0x0, 0x0, 0x0)
src/github.com/mholt/caddy/vendor/github.com/miekg/dns/clientconfig.go:86 +0xad6
github.com/mholt/caddy/vendor/github.com/xenolf/lego/acme.getNameservers(0xbb4739, 0x10, 0xfeaf20, 0x2, 0x2, 0xf77460, 0xc42004c2c0, 0xc420043f50)
src/github.com/mholt/caddy/vendor/github.com/xenolf/lego/acme/dns_challenge.go:40 +0x4d
github.com/mholt/caddy/vendor/github.com/xenolf/lego/acme.init()
src/github.com/mholt/caddy/vendor/github.com/xenolf/lego/acme/dns_challenge.go:33 +0x12d
github.com/mholt/caddy/caddy/caddymain.init()
:1 +0x75
main.init()
:1 +0x44
panic: runtime error: slice bounds out of range

goroutine 1 [running]:
github.com/mholt/caddy/vendor/github.com/miekg/dns.ClientConfigFromFile(0xbb4739, 0x10, 0x0, 0x0, 0x0)
src/github.com/mholt/caddy/vendor/github.com/miekg/dns/clientconfig.go:86 +0xad6
github.com/mholt/caddy/vendor/github.com/xenolf/lego/acme.getNameservers(0xbb4739, 0x10, 0xfeaf20, 0x2, 0x2, 0xf77460, 0xc42004c2c0, 0xc420043f50)
src/github.com/mholt/caddy/vendor/github.com/xenolf/lego/acme/dns_challenge.go:40 +0x4d
github.com/mholt/caddy/vendor/github.com/xenolf/lego/acme.init()
src/github.com/mholt/caddy/vendor/github.com/xenolf/lego/acme/dns_challenge.go:33 +0x12d
github.com/mholt/caddy/caddy/caddymain.init()
:1 +0x75
main.init()
:1 +0x44
panic: runtime error: slice bounds out of range
`

[nightah]

I do not have this issue with Arch Linux and Docker 20.10.1.
Can you retest with 20.10.1 and report your findings?

Also it's probably worth asking what Architecture is the machine you are running dockprom on?

[joesixpack]

I'm on Ubuntu 20.04 LTS amd64, but that newer Docker .1 update probably fixed things. I've already switched to Caddy v2 though.

[nightah]

Sure well either way I don't believe this is reproducible and isn't an issue with Caddy either way.

If you find you are experiencing issues again let me know and we can reopen the issue.

[apit]

pop!os 20.10 amd64 docker 20.10.1 has this issue. using caddy:1.0.3 image fixed it

[bhumijgupta]

I had the same issue with Ubuntu 20.04 LTS amd64 config running on AWS EC2 instance.
Ended up porting the Caddyfile to Caddy v2 and using it.