playing with corruption postgres one file at a time

gistfile1.txt

playing with corruption

 initdb -D db1 --data-checksums 2>/dev/null >/dev/null
 pg_ctl -D db1 -l db1.log start
 psql <<EOF
create table t(col1 int primary key, col2 int);
create table t2(col1 int references t(col1) on update cascade on delete cascade);
insert into t select generate_series(1, 100);
insert into t2 select generate_series(1, 100);
EOF
pg_basebackup -D db2 -R -c fast -C -S db2 -d "port=5432"
echo 'port=5433' >> db2/postgresql.auto.conf
pg_ctl -D db1 -l db1.log stop
pg_ctl -D db2 -l db2.log stop
find db1 -type f | xargs -I% dd if=/dev/urandom of=% bs=8k count=10 conv=notrunc,noerror

lets recover db1
for fun ....(and then we know the need of replica/backup/what each folder has and log messages)