I typed `sudo apr install nginx-extras` and got:
```Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
nginx-extras : Depends: libnginx-mod-http-auth-pam (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed Depends: libnginx-mod-http-cache-purge (= 1.12.1-0+artful0) but it is not going to be installed Depends: libnginx-mod-http-dav-ext (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed Depends: libnginx-mod-http-echo (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed Depends: libnginx-mod-http-fancyindex (= 1.12.1-0+artful0) but it is not going to be installed Depends: libnginx-mod-http-geoip (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed Depends: libnginx-mod-http-headers-more-filter (= 1.12.1-0+artful0) but it is not going to be installed Depends: libnginx-mod-http-image-filter (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed Depends: libnginx-mod-http-lua (= 1.12.1-0+artful0) but it is not going to be installed Depends: libnginx-mod-http-perl (= 1.12.1-0+artful0) but it is not going to be installed Depends: libnginx-mod-http-subs-filter (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed Depends: libnginx-mod-http-uploadprogress (= 1.12.1-0+artful0) but it is not going to be installed Depends: libnginx-mod-http-upstream-fair (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed Depends: libnginx-mod-http-xslt-filter (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed Depends: libnginx-mod-mail (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed Depends: libnginx-mod-nchan (= 1.12.1-0+artful0) but it is not going to be installed Depends: libnginx-mod-stream (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed Depends: nginx-common (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed
E: Unable to correct problems, you have held broken packages.
`lsb_release -rd`:
```
Description: Ubuntu 17.10
Release: 17.10
```
`apt-cache policy nginx-extras`: 12.1-0+ artful0 500 ppa.launchpad. net/nginx/ stable/ ubuntu artful/main amd64 Packages 12.1-0ubuntu2 500 ru.archive. ubuntu. com/ubuntu artful/universe amd64 Packages
```
nginx-extras:
Installed: (none)
Candidate: 1.12.1-0+artful0
Version table:
1.
500 http://
1.
500 http://
```
I typed `sudo apr install nginx-extras` and got:
```Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies: mod-http- auth-pam (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed
Depends: libnginx- mod-http- cache-purge (= 1.12.1-0+artful0) but it is not going to be installed
Depends: libnginx- mod-http- dav-ext (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed
Depends: libnginx- mod-http- echo (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed
Depends: libnginx- mod-http- fancyindex (= 1.12.1-0+artful0) but it is not going to be installed
Depends: libnginx- mod-http- geoip (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed
Depends: libnginx- mod-http- headers- more-filter (= 1.12.1-0+artful0) but it is not going to be installed
Depends: libnginx- mod-http- image-filter (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed
Depends: libnginx- mod-http- lua (= 1.12.1-0+artful0) but it is not going to be installed
Depends: libnginx- mod-http- perl (= 1.12.1-0+artful0) but it is not going to be installed
Depends: libnginx- mod-http- subs-filter (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed
Depends: libnginx- mod-http- uploadprogress (= 1.12.1-0+artful0) but it is not going to be installed
Depends: libnginx- mod-http- upstream- fair (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed
Depends: libnginx- mod-http- xslt-filter (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed
Depends: libnginx-mod-mail (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed
Depends: libnginx-mod-nchan (= 1.12.1-0+artful0) but it is not going to be installed
Depends: libnginx-mod-stream (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed
Depends: nginx-common (= 1.12.1-0+artful0) but 1.12.1-0+zesty0 is to be installed
nginx-extras : Depends: libnginx-
E: Unable to correct problems, you have held broken packages.
```
`apt-mark showhold`: nothing.