Category Archives: Shell Related

Issues running npm & WSL2 (bad interpreter)

I started a new project and wanted to use node/npm inside of WSL2. However, when I tried to run npm inside of either Ubuntu 18 or 20, I got this error message:

mark@LAPTOP:~$ npm
-bash: /mnt/c/Program Files/nodejs/npm: /bin/sh^M: bad interpreter: No such file or directory

After a whole lot of searching, I came across this web page, https://stackoverflow.com/questions/63716587/in-wsl2-ubuntu-20-04-for-windows-10-nodejs-is-installed-but-npm-is-not-working which suggested updating the ~/.bashrc file to look like:

# strip out problematic Windows %PATH%
PATH=$(echo "$PATH" | sed -e 's/:\/mnt.*//g')

I added that to the VERY end of the file, and rebooted.

The next time I tried to run npm, I got this successful message instead:

mark@LAPTOP:~$ npm

Usage: npm <command>

where <command> is one of:
    access, adduser, audit, bin, bugs, c, cache, ci, cit,
    clean-install, clean-install-test, completion, config,
    create, ddp, dedupe, deprecate, dist-tag, docs, doctor,
    edit, explore, fund, get, help, help-search, hook, i, init,
    install, install-ci-test, install-test, it, link, list, ln,
    login, logout, ls, org, outdated, owner, pack, ping, prefix,
    profile, prune, publish, rb, rebuild, repo, restart, root,
    run, run-script, s, se, search, set, shrinkwrap, star,
    stars, start, stop, t, team, test, token, tst, un,
    uninstall, unpublish, unstar, up, update, v, version, view,
    whoami

npm <command> -h  quick help on <command>
npm -l            display full usage info
npm help <term>   search for help on <term>
npm help npm      involved overview

Specify configs in the ini-formatted file:
    /home/mark/.npmrc
or on the command line via: npm <command> --key value
Config info can be viewed via: npm help config

npm@6.14.4 /usr/share/npm

Certbot: WWW and non-WWW certificates

Certbot is an awesome way to make sure your websites are secured with encryption and HTTPS.

It’s considered a best practice to have only 1 canonical version of a URL. But when you do that, you can run into issues where you get certificate mis-match errors. Here is an easy way to fix/prevent that.

sudo certbot certonly  -d originaldomain.com -d www.originaldomain.com

However, if you forgot do add in the www the first time, or if you want to create other subdomains that might answer on the same virtualhost, you’ll need to expand your original certificate.

--expand tells Certbot to update an existing certificate with a new certificate that contains all of the old domains and one or more additional new domains.

sudo certbot certonly --expand -d originaldomain.com -d www.originaldomain.com -d new.originaldomain.com -d new2.originaldomain.com -d new3.originaldomain.com --dry-run

NOTE: use the –dry-run flag for testing if it gives you the correct output without errors then re-run the same command and remove –dry-run from the end.

Another instance of Certbot is already running

I’ve written before about Certbot and how wonderful it is. Recently I’ve come across a situation where certbot renewals aren’t going thru:

root@host:~# certbot renew --force-renewal
Another instance of Certbot is already running.

root@host:~# ps waux | grep certbot
root     20947  0.0  0.0   4500   744 ?        Ss   16:52   0:00 /bin/sh -c /usr/local/sbin/certbot-renew.sh
root     20949  0.0  0.0   4500   736 ?        S    16:52   0:00 /bin/sh /usr/local/sbin/certbot-renew.sh
root     20953  0.3  4.4 148704 45440 ?        S    16:52   0:00 /usr/bin/python3 /usr/bin/certbot renew --post-hook touch /var/lib/letsencrypt/updated
root     21049  0.0  0.0  12940  1012 pts/4    S+   16:54   0:00 grep --color=auto certbot

root@host:~# certbot --version
certbot 0.31.0

If I check the logfile /var/log/letsencrypt/letsencrypt.log I can see that it keeps on trying and trying to do renewals.

grep "random delay" /var/log/letsencrypt/letsencrypt.log

2020-04-14 16:16:02,526:INFO:certbot.renewal:Non-interactive renewal: random delay of 5 seconds
2020-04-14 16:17:02,135:INFO:certbot.renewal:Non-interactive renewal: random delay of 409 seconds
2020-04-14 16:24:01,684:INFO:certbot.renewal:Non-interactive renewal: random delay of 290 seconds
2020-04-14 16:29:01,744:INFO:certbot.renewal:Non-interactive renewal: random delay of 190 seconds
2020-04-14 16:33:02,261:INFO:certbot.renewal:Non-interactive renewal: random delay of 283 seconds
2020-04-14 16:38:01,813:INFO:certbot.renewal:Non-interactive renewal: random delay of 350 seconds
2020-04-14 16:44:01,613:INFO:certbot.renewal:Non-interactive renewal: random delay of 117 seconds
2020-04-14 16:46:02,187:INFO:certbot.renewal:Non-interactive renewal: random delay of 309 seconds
2020-04-14 16:52:01,834:INFO:certbot.renewal:Non-interactive renewal: random delay of 453 seconds

Here’s what I do next:

  1. find any running certbot processes.
  2. kill them (with -9) one by one
  3. find and lock files
  4. remove them
root@host:~# ps waux | grep cert
root     20947  0.0  0.0   4500   744 ?        Ss   16:52   0:00 /bin/sh -c /usr/local/sbin/certbot-renew.sh
root     20949  0.0  0.0   4500   736 ?        S    16:52   0:00 /bin/sh /usr/local/sbin/certbot-renew.sh
root     20953  0.1  4.4 148704 45440 ?        S    16:52   0:00 /usr/bin/python3 /usr/bin/certbot renew --post-hook touch /var/lib/letsencrypt/updated
root     21152  0.0  0.0  12940   936 pts/4    S+   16:57   0:00 grep --color=auto cert

root@host:~# kill -9 20947
root@host:~# kill -9 20949
root@host:~# kill -9 20953
root@host:~# find / -type f -name ".certbot.lock"
/var/lib/letsencrypt/.certbot.lock
/var/log/letsencrypt/.certbot.lock
/etc/letsencrypt/.certbot.lock

root@host:~# rm /var/lib/letsencrypt/.certbot.lock  /var/log/letsencrypt/.certbot.lock /etc/letsencrypt/.certbot.lock

Next, I want to uninstall it.

root@host:~# apt list --installed | grep certbot

WARNING: apt does not have a stable CLI interface. Use with caution in scripts.

certbot/xenial,now 0.31.0-1+ubuntu16.04.1+certbot+1 all [installed]
python3-acme/xenial,now 0.31.0-2+ubuntu16.04.6+certbot+2 all [installed,automatic]
python3-asn1crypto/xenial,now 0.22.0-2+ubuntu16.04.1+certbot+1 all [installed,automatic]

Next, I want to uninstall it:

root@host:~#  apt-get remove certbot
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  python3-acme python3-certbot python3-configargparse python3-funcsigs python3-future python3-icu python3-josepy
  python3-mock python3-parsedatetime python3-pbr python3-requests-toolbelt python3-rfc3339 python3-tz
  python3-zope.component python3-zope.event python3-zope.hookable python3-zope.interface
Use 'apt autoremove' to remove them.
The following packages will be REMOVED:
  certbot
0 upgraded, 0 newly installed, 1 to remove and 9 not upgraded.
After this operation, 39.9 kB disk space will be freed.
Do you want to continue? [Y/n]

Type in Y to continue, then after that, get rid of code you no longer need

root@mhs02:~#  apt-get remove certbot
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  python3-acme python3-certbot python3-configargparse python3-funcsigs python3-future python3-icu python3-josepy
  python3-mock python3-parsedatetime python3-pbr python3-requests-toolbelt python3-rfc3339 python3-tz
  python3-zope.component python3-zope.event python3-zope.hookable python3-zope.interface
Use 'apt autoremove' to remove them.
The following packages will be REMOVED:
  certbot
0 upgraded, 0 newly installed, 1 to remove and 9 not upgraded.
After this operation, 39.9 kB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database ... 158315 files and directories currently installed.)
Removing certbot (0.31.0-1+ubuntu16.04.1+certbot+1) ...
Processing triggers for man-db (2.7.5-1) ...
root@host:~# apt autoremove
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
  python3-acme python3-certbot python3-configargparse python3-funcsigs python3-future python3-icu python3-josepy
  python3-mock python3-parsedatetime python3-pbr python3-requests-toolbelt python3-rfc3339 python3-tz
  python3-zope.component python3-zope.event python3-zope.hookable python3-zope.interface
0 upgraded, 0 newly installed, 17 to remove and 9 not upgraded.
After this operation, 6,352 kB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database ... 158306 files and directories currently installed.)
Removing python3-certbot (0.31.0-1+ubuntu16.04.1+certbot+1) ...
Removing python3-acme (0.31.0-2+ubuntu16.04.6+certbot+2) ...
Removing python3-configargparse (0.11.0-1+certbot~xenial+1) ...
Removing python3-mock (1.3.0-2.1ubuntu1) ...
Removing python3-funcsigs (0.4-2) ...
Removing python3-parsedatetime (2.4-3+ubuntu16.04.1+certbot+3) ...
Removing python3-future (0.15.2-4+ubuntu16.04.1+certbot+3) ...
Removing python3-icu (1.9.2-2build1) ...
Removing python3-josepy (1.1.0-2+ubuntu16.04.1+certbot+1) ...
Removing python3-pbr (1.8.0-4ubuntu1) ...
Removing python3-requests-toolbelt (0.8.0-1+ubuntu16.04.1+certbot+1) ...
Removing python3-rfc3339 (1.0-4+certbot~xenial+1) ...
Removing python3-tz (2014.10~dfsg1-0ubuntu2) ...
Removing python3-zope.component (4.3.0-1+ubuntu16.04.1+certbot+3) ...
Removing python3-zope.event (4.2.0-1) ...
Removing python3-zope.hookable (4.0.4-4+ubuntu16.04.1+certbot+1) ...
Removing python3-zope.interface (4.3.2-1+ubuntu16.04.1+certbot+1) ...

Check to see if that removed the process

root@host:~# ps waux | grep cert
root     21304  0.0  0.0   4500   748 ?        Ss   17:01   0:00 /bin/sh -c /usr/local/sbin/certbot-renew.sh
root     21306  0.0  0.0   4500   776 ?        S    17:01   0:00 /bin/sh /usr/local/sbin/certbot-renew.sh
root     21310  0.2  4.7 157436 48228 ?        S    17:01   0:00 /usr/bin/python3 /usr/bin/certbot renew --post-hook touch /var/lib/letsencrypt/updated
root     22017  0.0  0.1  12940  1092 pts/4    S+   17:08   0:00 grep --color=auto cert
root@host:~# ls /usr/local/sbin
certbot-renew.sh

root@host:~#  mv /usr/local/sbin/certbot-renew.sh   /usr/local/sbin/certbot-renew.sh.hide

Triple check nothings running

root@mhs02:~# ps waux | grep cert
root     22118  0.0  0.1  12940  1020 pts/4    S+   17:09   0:00 grep --color=auto cert

Follow the instructions at:
https://certbot.eff.org/instructions on how to install certbot for your installation.

sudo apt-get install certbot python-certbot-apache

Finally, let’s check the server uptime, check the expiration date of a site running on this server, gracefully restart apache, then check the expiration date again:

root@host:~# apachectl status | grep uptime
   Server uptime: 11 days 22 hours 45 minutes 34 seconds

root@host:~# echo | openssl s_client -servername www.example.org -connect www.example.org:443 2>/dev/null | openssl x509 -noout -dates
notBefore=Mar  3 16:27:55 2020 GMT
notAfter=Jun  1 16:27:55 2020 GMT

root@host:~# apachectl graceful
[Tue Apr 14 17:17:24.937566 2020] [so:warn] [pid 26644] AH01574: module security2_module is already loaded, skipping

root@host:~# apachectl status | egrep 'uptime|Restart'
   Restart Time: Thursday, 02-Apr-2020 18:29:10 UTC
   Server uptime: 11 days 22 hours 52 minutes 3 seconds


root@host:~# echo | openssl s_client -servername www.example.org -connect www.example.org:443 2>/dev/null | openssl x509 -noout -dates
notBefore=Apr 14 16:13:15 2020 GMT
notAfter=Jul 13 16:13:15 2020 GMT

Success! We can see that the new renewal dates are in place.

To make sure that renewals happen automatically, I like to have this crontab in place:

# Let's keep let's encrypt ssl certs up to date.
31 3,15 * * * /usr/bin/certbot renew --quiet

On Ubuntu 13+ and higher, /etc/bash_completion.d/git is now git-prompt

In this previous post I wrote about how to get some git branch information into your shell. That was written back when Ubuntu 12 LTS was the standard.

I recently upgraded a box to Ubuntu 16 LTS, and this information went away. 🙁

I discovered via trial and error, that the call that’s needed in .bashrc is now:

## To show you what branch you are in as you move around git repos
##
if [ -f /etc/bash_completion.d/git-prompt ]; then
. /etc/bash_completion.d/git-prompt
PS1='\[\u@\h \e[33m\]\w\[\e[0m\] $(__git_ps1 " (%s)")\n\$ '
fi


/etc/bash_completion.d/git is now: /etc/bash_completion.d/git-prompt

My favorite way to run screen

First, make sure you have screen installed:

[bash]
$ sudo apt-get install screen
[/bash]

Then, create a .screenrc file with the following in it:
[bash]
screen -t root sudo su –
screen -t bash2
screen -t bash3

select 0
startup_message off

caption always "%{= kw}%-w%{= bw}%n %t%{-}%+w %-= @%H – %c – (%l)"
#
# Call via: screen -R -e^Hh -d
#
# to change the strings, look at:
# http://www.gnu.org/software/screen/manual/screen.html#String-Escapes
#
# to test your changes, you can either copy the above line, the do
# CTRL-H : and then paste in the line above
#
# or, CTRL-H :source ~/.screenrc
[/bash]

Lastly, start up screen:
[bash]
screen -R -e^Hh -d
[/bash]

This let’s you switch screens by pressing CTRL-H and then SPACEBAR. (I found that I use CTRL-A far too much to let that be the standard screen key binding)

Git – automagically add modified files and rm deleted files

Sometimes a script will upgrade/add/modify/delete a large swath of files (possibly due to an upgrade-type script). If you are lazy, then you’ll want a script to help you commit those files. Here’s what I’ve come up with:

To perform a git add to all modified files:
[bash]
for file in `git status | grep modified | cut -d ":" -f 2`; do git add $file; done
[/bash]

To perform a git rm to all modified files:
[bash]
for file in `git status | grep deleted | cut -d ":" -f 2`; do git rm $file; done
[/bash]