Startup is really slow for all Cygwin applications

Eventually I found what causes this issue, but I'm still not sure why. Cygwin works for other people in same environment very well.

Cause: On the start of every Cygwin application it tries to get credentials as it is described in etc/nsswitch.conf file. For some reason, it takes a lots of time for my account as it contacts with several Active Directory domain controllers via LDAP.

Solution 1: You can save the current user and group in etc/passwd and etc/group files and set Cygwin to check them before Active Directory.

1. Start mintty.exe and wait till it opens
2. Run mkpasswd -c and save its output to etc/passwd file (you will have to create it, output should be one line)
3. Run mkgroup -c and save its output to etc/group file (you will have to create it, output should be one line)
4. Open etc/nsswitch.conf and write

nsswitch.conf contents:

passwd: files # dbgroup:  files # db

Now your Cygwin should start immediately.

Solution 2: There is special CygServer application, shipped with Cygwin, which can be started as an NT service or as a simple process (just run usr/sbin/cygserver.exe). It caches credentials and propagates them to every next Cygwin process while cygserver is running.

Add it to startup or start it before your Cygwin session and you're good — cygserver startup will take time, but every next Cygwin process will start immediately.

Is it your case? I want to share my investigation steps, so you could check, if your case is same to mine.

• Install MS Network Monitor as it is able to show traffic from a specific process. Run it as administrator.
• Create New capture tab and click Start (you don't have to add any filters or anything).
• Start mintty and you will see its connections in netmon:
• You will see list of mintty connections in the tree view on the left and TCP and LDAP frames on the right after selecting on of those connections.
• Additionally, you can get name of those remote machines by IP address. Run nbtstat -a 8.8.8.8 in command line (replace 8.8.8.8 by one of IP addresses from netmon).

Going deeper: I'm still playing with etc/nsswitch.conf file to get local credentials or maybe cached ones so it will run faster without cygserver. But no luck yet.

Here's what worked for me.

1. Launch Cygwin terminal and then run the following two strings.

   mkpasswd -c > /etc/passwdmkgroup -c > /etc/group

2. Edit your "/etc/nsswitch.conf" file to contain the following two lines.

   passwd:   files # dbgroup:    files # db

3. Relaunch Cygwin.

Cygwin opens quickly.

If you are on a network with a large AD directory mkpasswd will take a lot of time (several days in my case). So consider using:

mkpasswd -c -l > /etc/passwdmkgroup -c -l > /etc/group -l,--local [machine]    Print local user accounts of \"machine\",                         from local machine if no machine specified.                         Automatically adding machine prefix for local                         machine depends on settings in /etc/nsswitch.conf.