Files
neon/compute/vm-image-spec-bullseye.yaml
Alexey Kondratov ab14521ea5 fix(compute): Turn off database collector in postgres_exporter (#12684)
## Problem

`postgres_exporter` has database collector enabled by default and it
doesn't filter out invalid databases, see

06a553c816/collector/pg_database.go (L67)
so if it hits one, it starts spamming logs
```
ERROR:  [NEON_SMGR] [reqid d9700000018] could not read db size of db 705302 from page server at lsn 5/A2457EB0
```

## Summary of changes

We don't use `pg_database_size_bytes` metric anyway, see

5e19b3fd89/apps/base/compute-metrics/scrape-compute-pg-exporter-neon.yaml (L29)
so just turn it off by passing `--no-collector.database`.
2025-07-24 11:52:31 +00:00

165 lines
7.2 KiB
YAML

# Supplemental file for neondatabase/autoscaling's vm-builder, for producing the VM compute image.
---
commands:
- name: cgconfigparser
user: root
sysvInitAction: sysinit
shell: 'cgconfigparser -l /etc/cgconfig.conf -s 1664'
# restrict permissions on /neonvm/bin/resize-swap, because we grant access to compute_ctl for
# running it as root.
- name: chmod-resize-swap
user: root
sysvInitAction: sysinit
shell: 'chmod 711 /neonvm/bin/resize-swap'
- name: chmod-set-disk-quota
user: root
sysvInitAction: sysinit
shell: 'chmod 711 /neonvm/bin/set-disk-quota'
- name: pgbouncer
user: postgres
sysvInitAction: respawn
shell: '/usr/local/bin/pgbouncer /etc/pgbouncer.ini 2>&1 > /dev/virtio-ports/tech.neon.log.0'
- name: local_proxy
user: postgres
sysvInitAction: respawn
shell: 'RUST_LOG="error" /usr/local/bin/local_proxy --config-path /etc/local_proxy/config.json --pid-path /etc/local_proxy/pid --http 0.0.0.0:10432'
- name: postgres-exporter
user: nobody
sysvInitAction: respawn
# Turn off database collector (`--no-collector.database`), we don't use `pg_database_size_bytes` metric anyway, see
# https://github.com/neondatabase/flux-fleet/blob/5e19b3fd897667b70d9a7ad4aa06df0ca22b49ff/apps/base/compute-metrics/scrape-compute-pg-exporter-neon.yaml#L29
# but it's enabled by default and it doesn't filter out invalid databases, see
# https://github.com/prometheus-community/postgres_exporter/blob/06a553c8166512c9d9c5ccf257b0f9bba8751dbc/collector/pg_database.go#L67
# so if it hits one, it starts spamming logs
# ERROR: [NEON_SMGR] [reqid d9700000018] could not read db size of db 705302 from page server at lsn 5/A2457EB0
shell: 'DATA_SOURCE_NAME="user=cloud_admin sslmode=disable dbname=postgres application_name=postgres-exporter pgaudit.log=none" /bin/postgres_exporter --no-collector.database --config.file=/etc/postgres_exporter.yml'
- name: pgbouncer-exporter
user: postgres
sysvInitAction: respawn
shell: '/bin/pgbouncer_exporter --pgBouncer.connectionString="postgres:///pgbouncer?host=/tmp&port=6432&dbname=pgbouncer&user=pgbouncer"'
- name: sql-exporter
user: nobody
sysvInitAction: respawn
shell: '/bin/sql_exporter -config.file=/etc/sql_exporter.yml -web.listen-address=:9399'
- name: sql-exporter-autoscaling
user: nobody
sysvInitAction: respawn
shell: '/bin/sql_exporter -config.file=/etc/sql_exporter_autoscaling.yml -web.listen-address=:9499'
# Rsyslog by default creates a unix socket under /dev/log . That's where Postgres sends logs also.
# We run syslog with postgres user so it can't create /dev/log. Instead we configure rsyslog to
# use a different path for the socket. The symlink actually points to our custom path.
- name: rsyslogd-socket-symlink
user: root
sysvInitAction: sysinit
shell: "ln -s /var/db/postgres/rsyslogpipe /dev/log"
- name: rsyslogd
user: postgres
sysvInitAction: respawn
shell: '/usr/sbin/rsyslogd -n -i /var/run/rsyslogd/rsyslogd.pid -f /etc/compute_rsyslog.conf'
shutdownHook: |
su -p postgres --session-command '/usr/local/bin/pg_ctl stop -D /var/db/postgres/compute/pgdata -m fast --wait -t 10'
files:
- filename: compute_ctl-sudoers
content: |
# Reverse hostname lookup doesn't currently work, and isn't needed anyway when all
# the rules use ALL as the hostname. Avoid the pointless lookups and the "unable to
# resolve host" log messages that they generate.
Defaults !fqdn
# Allow postgres user (which is what compute_ctl runs as) to run /neonvm/bin/resize-swap
# and /neonvm/bin/set-disk-quota as root without requiring entering a password (NOPASSWD),
# regardless of hostname (ALL)
#
# Also allow it to shut down the VM. The fast_import job does that when it's finished.
postgres ALL=(root) NOPASSWD: /neonvm/bin/resize-swap, /neonvm/bin/set-disk-quota, /neonvm/bin/poweroff, /usr/sbin/rsyslogd
- filename: cgconfig.conf
content: |
# Configuration for cgroups in VM compute nodes
group neon-postgres {
perm {
admin {
uid = postgres;
}
task {
gid = users;
}
}
memory {}
}
# Create dummy rsyslog config, because it refuses to start without at least one action configured.
# compute_ctl will rewrite this file with the actual configuration, if needed.
- filename: compute_rsyslog.conf
content: |
# Syslock.Name specifies a non-default pipe location that is writeable for the postgres user.
module(load="imuxsock" SysSock.Name="/var/db/postgres/rsyslogpipe") # provides support for local system logging
*.* /dev/null
$IncludeConfig /etc/rsyslog.d/*.conf
build: |
# Build cgroup-tools
#
# At time of writing (2023-03-14), debian bullseye has a version of cgroup-tools (technically
# libcgroup) that doesn't support cgroup v2 (version 0.41-11). Unfortunately, the vm-monitor
# requires cgroup v2, so we'll build cgroup-tools ourselves.
ARG BULLSEYE_SLIM_SHA=sha256:e831d9a884d63734fe3dd9c491ed9a5a3d4c6a6d32c5b14f2067357c49b0b7e1
FROM debian@$BULLSEYE_SLIM_SHA as libcgroup-builder
ENV LIBCGROUP_VERSION=v2.0.3
RUN set -exu \
&& apt update \
&& apt install --no-install-recommends -y \
git \
ca-certificates \
automake \
cmake \
make \
gcc \
byacc \
flex \
libtool \
libpam0g-dev \
&& git clone --depth 1 -b $LIBCGROUP_VERSION https://github.com/libcgroup/libcgroup \
&& INSTALL_DIR="/libcgroup-install" \
&& mkdir -p "$INSTALL_DIR/bin" "$INSTALL_DIR/include" \
&& cd libcgroup \
# extracted from bootstrap.sh, with modified flags:
&& (test -d m4 || mkdir m4) \
&& autoreconf -fi \
&& rm -rf autom4te.cache \
&& CFLAGS="-O3" ./configure --prefix="$INSTALL_DIR" --sysconfdir=/etc --localstatedir=/var --enable-opaque-hierarchy="name=systemd" \
# actually build the thing...
&& make install
merge: |
# tweak nofile limits
RUN set -e \
&& echo 'fs.file-max = 1048576' >>/etc/sysctl.conf \
&& test ! -e /etc/security || ( \
echo '* - nofile 1048576' >>/etc/security/limits.conf \
&& echo 'root - nofile 1048576' >>/etc/security/limits.conf \
)
# Allow postgres user (compute_ctl) to run swap resizer.
# Need to install sudo in order to allow this.
#
# Also, remove the 'read' permission from group/other on /neonvm/bin/resize-swap, just to be safe.
RUN set -e \
&& apt update \
&& apt install --no-install-recommends -y \
sudo \
&& rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
COPY compute_ctl-sudoers /etc/sudoers.d/compute_ctl-sudoers
COPY cgconfig.conf /etc/cgconfig.conf
RUN set -e \
&& chmod 0644 /etc/cgconfig.conf
COPY compute_rsyslog.conf /etc/compute_rsyslog.conf
RUN chmod 0666 /etc/compute_rsyslog.conf
RUN mkdir /var/log/rsyslog && chown -R postgres /var/log/rsyslog
COPY --from=libcgroup-builder /libcgroup-install/bin/* /usr/bin/
COPY --from=libcgroup-builder /libcgroup-install/lib/* /usr/lib/
COPY --from=libcgroup-builder /libcgroup-install/sbin/* /usr/sbin/