Custom Query (2297 matches)

Hi, I have the following simple configuration:

/ # cat /etc/nginx/conf.d/nginx.conf
server {
    listen 8080;
    server_name $hostname;
    location / {
        root /usr/share/nginx/html;
        index index.html;
        try_files $uri $uri/ /index.html;
    }
    location /api/ {
        error_log  /var/log/nginx/api-error.log debug;
        resolver kube-dns.kube-system.svc.cluster.local valid=10s;
        set $target todo-list-backend-svc.default.svc.cluster.local;
        proxy_pass http://$target;
    }

Which gives me the following error:

/ # nginx -s reload
2023/08/26 11:16:25 [emerg] 60#60: host not found in resolver "kube-dns.kube-system.svc.cluster.local" in /etc/nginx/conf.d/nginx.conf:11
nginx: [emerg] host not found in resolver "kube-dns.kube-system.svc.cluster.local" in /etc/nginx/conf.d/nginx.conf:11

I've checked that "kube-dns.kube-system.svc.cluster.local" can be resolved locally:

/ # nslookup kube-dns.kube-system.svc.cluster.local
Server:		10.96.0.10
Address:	10.96.0.10:53


Name:	kube-dns.kube-system.svc.cluster.local
Address: 10.96.0.10

This is my /etc/resolv.conf:

/ # cat /etc/resolv.conf
nameserver 10.96.0.10
search default.svc.cluster.local svc.cluster.local cluster.local localdomain
options ndots:5

When I remove the "svc.cluster.local" from the DNS name, nginx is reloaded without any issue:

/ # cat /etc/nginx/conf.d/nginx.conf
server {
    listen 8080;
    server_name $hostname;
    location / {
        root /usr/share/nginx/html;
        index index.html;
        try_files $uri $uri/ /index.html;
    }
    location /api/ {
        error_log  /var/log/nginx/api-error.log debug;
        resolver kube-dns.kube-system valid=30s;
        set $target todo-list-backend-svc.default.svc.cluster.local;
        proxy_pass http://$target;
    }
/ # nginx -s reload
2023/08/26 11:20:03 [notice] 67#67: signal process started
/ #

So, what is going wrong here? It looks like resolver is unable to deal with long DNS names.

If a initial packet with zero-length odcid is accpeted, nginx will create a quic connection state machine and insert a temp ngx_quic_socket_t object with the odcid in the red-black tree, but this will result nginx can not process other initial packet with zero-length odcid from different peer?

Nginx's current default branch (revision hash 44536076405cf79ebdd82a6a0ab27bb3aed86b04) fails to build with clang on Alpine Linux because of Werror and Wsign-compare.

Steps to reproduce:

0. Get a fresh Alpine Linux container:

docker run --rm --workdir /repro -it alpine:3.18.0

1. Get dependencies:

apk add mercurial clang musl-dev pcre-dev zlib-dev make

2. Clone nginx:

hg clone "https://hg.nginx.org/nginx"

3. Configure:

cd nginx && ./auto/configure --with-cc=clang

4. Try to build:

make

5. Observe the warning->error that halts the build:

   make -f objs/Makefile
   make[1]: Entering directory '/repro/nginx'
   ...
   clang -c -pipe  -O -Wall -Wextra -Wpointer-arith -Wconditional-uninitialized -Wno-unused-parameter -Werror -g  -I src/core -I src/event -I src/event/modules -I src/event/quic -I src/os/unix -I objs \
   	-o objs/src/event/ngx_event_udp.o \
   	src/event/ngx_event_udp.c
   src/event/ngx_event_udp.c:143:25: error: comparison of integers of different signs: 'unsigned long' and 'long' [-Werror,-Wsign-compare]
                    cmsg = CMSG_NXTHDR(&msg, cmsg))
                           ^~~~~~~~~~~~~~~~~~~~~~~
   /usr/include/sys/socket.h:358:44: note: expanded from macro 'CMSG_NXTHDR'
           __CMSG_LEN(cmsg) + sizeof(struct cmsghdr) >= __MHDR_END(mhdr) - (unsigned char *)(cmsg) \
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   1 error generated.
   make[1]: *** [objs/Makefile:641: objs/src/event/ngx_event_udp.o] Error 1
   make[1]: Leaving directory '/repro/nginx'
   make: *** [Makefile:10: build] Error 2
   

The build succeeds with GCC 12.2.1 on Alpine, and with clang 16 on Debian. It's only clang 16 on Alpine that fails.