Skip to content

Ignore DHCP-supplied DNS search domains on Ubuntu #196

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Draft
samestep wants to merge 1 commit into
base: main
Choose a base branch
from
Draft

Ignore DHCP-supplied DNS search domains on Ubuntu #196

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
15 changes: 15 additions & 0 deletions README.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -203,6 +203,21 @@ Avoid ten-second hangs by enabling Ubuntu to resolve the local hostname:
echo "127.0.1.1 $(hostname)" | sudo tee -a /etc/hosts
```

Avoid another class of ten-second hangs by telling Ubuntu to ignore the DNS search domains it gets over DHCP. The host's `vmnet` DHCP server relays the Mac's own resolver search domains (e.g. leftover `*.cmu.edu` entries from a network the laptop was once on) into the VM, and Ubuntu appends them to public names like `github.com`; if any of those domains points at an unreachable resolver, every lookup stalls for ten seconds. Drop them:

```sh
sudo tee /etc/netplan/60-no-search-domains.yaml <<'EOF' >/dev/null
network:
version: 2
ethernets:
all:
dhcp4-overrides:
use-domains: false
EOF
sudo chmod 600 /etc/netplan/60-no-search-domains.yaml
sudo netplan apply
```

Next, install Nix:

```sh
Expand Down