On local server start error says the port is already in use

[thesillystudent]

• While restarting the Django development server the error comes up which says that the port is already in use
• Server should restart normally as it does on cmd
• Server doesn't restart
• Windows build number - 14393.10

[misenesi]

When you run in another cmd.exe:

netstat -anb

Do you see the port being occupied? If you run in bash:

lsof -i :8000

Can you see who is using that port?

[dvlsg]

I also have this issue, but with redis. lsof -i :6379 doesn't report that anything is already using the port. netstat -anb from cmd.exe confirms the same.

Output from running a newly built redis-server (with default configuration) states:
Creating server TCP listening socket *:6379: bind: Address already in use

Same OS build number (14393.10), Windows 10 x64 Anniversary Update.

[misenesi]

Could you provide repro steps along with strace please, so I can look more into it?

More here:
https://github.com/Microsoft/BashOnWindows/blob/master/CONTRIBUTING.md

[dvlsg]

Of course! I can open a separate ticket if you think the issues are unrelated.

Here is the gist containing the strace created with strace redis-server &> redis-server-strace.txt

https://gist.github.com/dvlsg/6232d2adde9971a3479c848ce5b2704b

And here are the steps I used to install redis (taken from their website, and slightly modified to get around some issues I ran into). So to reproduce, from start to finish:

wget http://download.redis.io/redis-stable.tar.gz
tar xvzf redis-stable.tar.gz
cd redis-stable/deps
# i had to first make each dep manually, for some reason.
make geohash-int hiredis jemalloc linenoise lua
cd ..
make
cd src
redis-server

Here's the console output from redis-server, at that point:

6878:C 03 Aug 11:55:46.998 # Warning: no config file specified, using the default config. In order to specify a config file use redis-server /path/to/redis.conf
6878:M 03 Aug 11:55:46.999 * Increased maximum number of open files to 10032 (it was originally set to 2048).
6878:M 03 Aug 11:55:46.999 # Creating Server TCP listening socket *:6379: bind: Address already in use

And just to reconfirm, the following two commands result in empty outputs (I also looked through the netstat by hand, just in case I was misremembering how findstr worked);

netstat -anb | findstr 6379
lsof -i :6379

[mmalek06]

Any info on what's the expected time of fix release? I'm experiencing the same exact issue as the guys.

[sunilmut]

This looks related to #996. Essentially, the problem is lack of full support for IPV6_V6ONLY. See #996 for detailed analysis. Apologize for the inconvinience. We are actively working with the Windows networking team to address this issue and expect it to be fixed shortly. But as a workaround, you can try using only IPV4 or different ports for IPV4 and IPV6.

From the trace shared by @dvlsg
setsockopt(4, SOL_IPV6, **IPV6_V6ONLY**, [1], 4) = 0 setsockopt(4, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 bind(4, {sa_family=AF_INET6, sin6_port=**htons(6379),** inet_pton(AF_INET6, "::", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, 28) = 0 socket(PF_INET, SOCK_STREAM, IPPROTO_TCP) = 5 setsockopt(5, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 bind(5, {sa_family=AF_INET, sin_port=**htons(6379**), sin_addr=inet_addr("0.0.0.0")}, 16) = -1 EADDRINUSE (Address already in use)

[sunilmut]

With the help of the Windows networking team, we were able to fully implement the IPV6_V6ONLY flag. I was able to get the redis-server up and running by following the repro about by @dvlsg. The fix is still in our dev branch, but should soon hit the release branch.

[sunilmut]

Just FYI that the IPV6_V6ONLY issue is fixed in 14936 (see release notes)

[sunilmut]

Closing this out. If this is still failing for people in 14942+, do let us know.