Tripwire
1.Install
# dnf -y install tripwire
2.Passphrase setting
# tripwire-setup-keyfiles
----------------------------------------------
The Tripwire site and local passphrases are used to sign a variety of
files, such as the configuration, policy, and database files.
Passphrases should be at least 8 characters in length and contain both
letters and numbers.
See the Tripwire manual for more information.
----------------------------------------------
Creating key files...
(When selecting a passphrase, keep in mind that good passphrases typically
have upper and lower case letters, digits and punctuation marks, and are
at least 8 characters in length.)
Enter the site keyfile passphrase: ←Enter any "Site Passphrase"
Verify the site keyfile passphrase: ←Enter "Site Passphrase" again
Generating key (this may take several minutes)...Key generation complete.
(When selecting a passphrase, keep in mind that good passphrases typically
have upper and lower case letters, digits and punctuation marks, and are
at least 8 characters in length.)
Enter the local keyfile passphrase: ←Enter any "local passphrase"
Verify the local keyfile passphrase: ←Enter "Local Passphrase" again
Generating key (this may take several minutes)...Key generation complete.
----------------------------------------------
Signing configuration file...
Please enter your site passphrase: ←Enter "Site Passphrase"
Wrote configuration file: /etc/tripwire/tw.cfg
A clear-text version of the Tripwire configuration file:
/etc/tripwire/twcfg.txt
has been preserved for your inspection. It is recommended that you
move this file to a secure location and/or encrypt it in place (using a
tool such as GPG, for example) after you have examined it.
----------------------------------------------
Signing policy file...
Please enter your site passphrase: ←Enter "Site Passphrase"
Wrote policy file: /etc/tripwire/tw.pol
A clear-text version of the Tripwire policy file:
/etc/tripwire/twpol.txt
has been preserved for your inspection. This implements a minimal
policy, intended only to test essential Tripwire functionality. You
should edit the policy file to describe your system, and then use
twadmin to generate a new signed copy of the Tripwire policy.
Once you have a satisfactory Tripwire policy file, you should move the
clear-text version to a secure location and/or encrypt it in place
(using a tool such as GPG, for example).
Now run "tripwire --init" to enter Database Initialization Mode. This
reads the policy file, generates a database based on its contents, and
then cryptographically signs the resulting database. Options can be
entered on the command line to specify which policy, configuration, and
key files are used to create the database. The filename for the
database can be specified as well. If no options are specified, the
default values from the current configuration file are used.
3.Tripwire Configuration
①Configuration File Edit
# vi /etc/tripwire/twcfg.txt
# Line 9 : Set to true
LOOSEDIRECTORYCHECKING =true
# Line 12 : Switch to the most detailed report
REPORTLEVEL =4
②Create a Tripwire configuration file (cryptographically signed version)
# twadmin -m F -c /etc/tripwire/tw.cfg -S /etc/tripwire/site.key /etc/tripwire/twcfg.txt
Please enter your site passphrase: ←Enter site passphrase
Wrote configuration file: /etc/tripwire/tw.cfg
③Delete Tripwire configuration file (text version)
# rm -f /etc/tripwire/twcfg.txt
④Policy File Settings
# cd /etc/tripwire/
# vi twpolmake.pl
Contents of twpolmake.pl
#!/usr/bin/perl
# Tripwire Policy File customize tool
#
$POLFILE=$ARGV[0];
open(POL,"$POLFILE") or die "open error: $POLFILE" ;
my($myhost,$thost) ;
my($sharp,$tpath,$cond) ;
my($INRULE) = 0 ;
while (<POL>) {
chomp;
if (($thost) = /^HOSTNAME\s*=\s*(.*)\s*;/) {
$myhost = `hostname` ; chomp($myhost) ;
if ($thost ne $myhost) {
$_="HOSTNAME=\"$myhost\";" ;
}
}
elsif ( /^{/ ) {
$INRULE=1 ;
}
elsif ( /^}/ ) {
$INRULE=0 ;
}
elsif ($INRULE == 1 and ($sharp,$tpath,$cond) = /^(\s*\#?\s*)(\/\S+)\b(\s+->\s+.+)$/) {
$ret = ($sharp =~ s/\#//g) ;
if ($tpath eq '/sbin/e2fsadm' ) {
$cond =~ s/;\s+(tune2fs.*)$/; \#$1/ ;
}
if (! -s $tpath) {
$_ = "$sharp#$tpath$cond" if ($ret == 0) ;
}
else {
$_ = "$sharp$tpath$cond" ;
}
}
print "$_\n" ;
}
close(POL) ;
⑤Policy File Optimizations
# perl /etc/tripwire/twpolmake.pl /etc/tripwire/twpol.txt > /etc/tripwire/twpol.txt.new
⑥Create policy file (cryptographically signed version) based on optimized policy file
# twadmin -m P -c /etc/tripwire/tw.cfg -p /etc/tripwire/tw.pol -S /etc/tripwire/site.key /etc/tripwire/twpol.txt.new
Please enter your site passphrase: ←Enter the site passphrase
Wrote policy file: /etc/tripwire/tw.pol
⑦Create database and check operation
# tripwire -m i -s -c /etc/tripwire/tw.cfg
Please enter your local passphrase: ←Enter the local passphrase
Create test files
# echo test > /root/test.txt
Check Tripwire operation
# tripwire -m c -s -c /etc/tripwire/tw.cfg
If it is displayed as below, it is OK
Open Source Tripwire(R) 2.4.3.7 Integrity Check Report
Report generated by: root
Report created on: Thu 12 Nov 2026 03:25:32 PM JST
Database last updated on: Never
===============================================================================
Report Summary:
===============================================================================
Host name: Lepard
Host IP address: 192.168.11.83
Host ID: None
Policy file used: /etc/tripwire/tw.pol
Configuration file used: /etc/tripwire/tw.cfg
Database file used: /var/lib/tripwire/Lepard.twd
Command line used: tripwire -m c -s -c /etc/tripwire/tw.cfg
===============================================================================
Rule Summary:
===============================================================================
-------------------------------------------------------------------------------
Section: Unix File System
-------------------------------------------------------------------------------
Rule Name Severity Level Added Removed Modified
--------- -------------- ----- ------- --------
User binaries 66 0 0 0
Tripwire Binaries 100 0 0 0
Operating System Utilities 100 0 0 0
Libraries 66 0 0 0
OS executables and libraries 100 0 0 0
File System and Disk Administraton Programs
100 0 0 0
Networking Programs 100 0 0 0
System Administration Programs 100 0 0 0
Critical Utility Sym-Links 100 0 0 0
Shell Binaries 100 0 0 0
* Tripwire Data Files 100 1 0 0
System boot changes 100 0 0 0
Security Control 100 0 0 0
Login Scripts 100 0 0 0
Critical configuration files 100 0 0 0
Kernel Administration Programs 100 0 0 0
Hardware and Device Control Programs
100 0 0 0
Application Information Programs
100 0 0 0
(/sbin/rtmon)
Critical system boot files 100 0 0 0
* Root config files 100 1 0 0
Invariant Directories 66 0 0 0
Temporary directories 33 0 0 0
Critical devices 100 0 0 0
Total objects scanned: 53857
Total violations found: 2
===============================================================================
Object Summary:
===============================================================================
-------------------------------------------------------------------------------
# Section: Unix File System
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Rule Name: Tripwire Data Files (/var/lib/tripwire)
Severity Level: 100
-------------------------------------------------------------------------------
Added:
"/var/lib/tripwire/Lepard.twd"
-------------------------------------------------------------------------------
Rule Name: Root config files (/root)
Severity Level: 100
-------------------------------------------------------------------------------
Added:
"/root/test.txt"
===============================================================================
Error Report:
===============================================================================
No Errors
-------------------------------------------------------------------------------
*** End of report ***
Open Source Tripwire 2.4 Portions copyright 2000-2018 Tripwire, Inc. Tripwire is a registered
trademark of Tripwire, Inc. This software comes with ABSOLUTELY NO WARRANTY;
for details use --version. This is free software which may be redistributed
or modified only under certain conditions; see COPYING for details.
All rights reserved.
Delete test files
# rm -f /root/test.txt
⑧Tripwire: Create a script to periodically report results via email
# cd /var/www/system
# vi tripwire.sh
Contents of tripwire.sh
#!/bin/bash
PATH=/usr/sbin:/usr/bin:/bin:/usr/local/tripwire/sbin
# Passphrase Setup
LOCALPASS=xxxxx # Local Key Passphrase
SITEPASS=xxxxx # Site Key Passphrase
#Specify notification email address
MAIL="<your mailaddress> "
cd /etc/tripwire
# Tripwire Check Execution
tripwire -m c -s -c tw.cfg|mail -s "Tripwire(R) Integrity Check Report in `hostname`" $MAIL
# Policy File Update
twadmin -m p -c tw.cfg -p tw.pol -S site.key > twpol.txt
perl twpolmake.pl twpol.txt > twpol.txt.new
twadmin -m P -c tw.cfg -p tw.pol -S site.key -Q $SITEPASS twpol.txt.new > /dev/null
rm -f twpol.txt* *.bak
# Database Update
rm -f /usr/local/tripwire/lib/tripwire/*.twd*
tripwire -m i -s -c tw.cfg -P $LOCALPASS
# chmod 700 tripwire.sh
Add to cron
# crontab -e
0 3 * * * /var/www/system/tripwire.sh
Execute the following command and verify that the Tripwire execution results are notified to the specified email address.
# /var/www/system/tripwire.sh
Logwatch
①Install
# dnf -y install logwatch
②Edit configuration file
# cat /usr/share/logwatch/default.conf/logwatch.conf >> /etc/logwatch/conf/logwatch.conf
# vi /etc/logwatch/conf/logwatch.conf
# Lene 76 : Set "MailTo = root" as a comment and set the email address you want to receive notifications to the line below it.
#MailTo = root
MailTo = [Mail address]
# Per Line 115 : Set the level of detail for log notifications
#Detail = Low
Detail = High
③Output Logwatch reports
# logwatch --output stdout
It will appear as follows
################### Logwatch 7.15 (07/22/26) ####################
Processing Initiated: Thu Nov 12 15:37:53 2026
Date Range Processed: yesterday
( 2026-Nov-11 )
Period is day.
Detail Level of Output: 10
Type of Output/Format: stdout / text
Logfiles for Host: Lepard
##################################################################
--------------------- Kernel Audit Begin ------------------------
Number of audit daemon starts: 2
Number of audit daemon stops: 2
Number of audit initializations: 3
----------------------------Omission-----------------------
--------------------- Disk Space Begin ------------------------
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/fedora-root 15G 3.8G 12G 26% /
efivarfs 256K 75K 177K 30% /sys/firmware/efi/efivars
/dev/nvme0n1p2 2.0G 417M 1.6G 21% /boot
/dev/nvme0n1p1 599M 8.0M 591M 2% /boot/efi
---------------------- Disk Space End -------------------------
--------------------- lm_sensors output Begin ------------------------
nvme-pci-0b00
Adapter: PCI adapter
Composite: +29.9 C
---------------------- lm_sensors output End -------------------------
###################### Logwatch End #########################
④Test to see if the report arrives at the address you set. Check if you receive a log report email like the one above.
# /etc/cron.daily/0logwatch
Introduce disk usage check script
1 Script Creation
# cd /var/www/system
# vi disk_capacity_check.sh
Contents of disk_capacity_check.sh
#!/bin/bash
# Specify notification email address
MAIL="<Mail address>"
DVAL=`/bin/df / | /usr/bin/tail -1 | /bin/sed 's/^.* \([0-9]*\)%.*$/\1/'`
if [ $DVAL -gt 80 ]; then
echo "Disk usage alert: $DVAL %" | mail -s "Disk Space Alert in `hostname`" $MAIL
fi
Execution permission
# chmod 700 disk_capacity_check.sh
2 Execution Confirmation
①Check current usage rates
# df -h
It appears as follows
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/fedora-root 15G 3.8G 12G 26% /
devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs 1.9G 0 1.9G 0% /dev/shm
efivarfs 256K 75K 177K 30% /sys/firmware/efi/efivars
tmpfs 771M 3.6M 768M 1% /run
none 1.0M 0 1.0M 0% /run/credentials/systemd-journald.service
none 1.0M 0 1.0M 0% /run/credentials/systemd-resolved.service
tmpfs 1.9G 2.1M 1.9G 1% /tmp
/dev/nvme0n1p2 2.0G 417M 1.6G 21% /boot
/dev/nvme0n1p1 599M 8.0M 591M 2% /boot/efi
tmpfs 386M 4.0K 386M 1% /run/user/1000
②Create a dummy file to achieve at least 80% utilization(In the example, the name is dummyfile and it is about 10G.)
# dd if=/dev/zero of=dummyfile bs=1M count=10000
➂Run check scripts
# /var/www/system/disk_capacity_check.sh
You will receive an email to the email address you have set up, stating something like "Disk usage alert: 91%".
④Delete "dummyfile"
# rm dummyfile
⑤Periodic Execution Setting
# crontab -e
30 2 * * * /var/www/system/disk_capacity_check.sh
DNS Update
Whenever the internet connection is lost or the router reboots, causing the global IP address to change, you must access the dynamic DNS service to notify it of the new IP address.
Create a dedicated Python file and schedule it for regular execution via Cron.
This time, it's about DNS settings in Valuedomain.
# cd /var/www/system
# vi ddnsset.py
Content of ddnsset.py
#setddns.py
import requests
import ipaddress
from datetime import datetime
from pathlib import Path
# SETTING DATA
MY_DOMAIN = "example.jp" ←Self-hosted domain
MY_PASS = "xxxxxxxxxx" ←Password
MY_HOSTNAME = "xxxx" ←Host name
OUT_FILE = Path("/tmp/ipadress") ←IP Address Log File
def time_msg():
now = datetime.now()
return now.strftime("%Y/%m/%d %H:%M:%S")
def is_valid_ip(ip_str):
try:
ipaddress.ip_address(ip_str)
return True
except ValueError:
return False
def main():
# Check Global IP Address
url_get_ip = "https://dyn.value-domain.com/cgi-bin/dyn.fcg?ip"
try:
response = requests.get(url_get_ip, timeout=10)
response.raise_for_status()
current_ip = response.text.strip()
except requests.RequestException as e:
print(f"{time_msg()} Failed to get IP: {e}")
return
# IP check
mssg = time_msg()
if not current_ip:
print(f"{mssg} invalid IP NULL")
return
if not is_valid_ip(current_ip):
print(f"{mssg} invalid IP={current_ip}")
return
# Read previous IP
previous_ip = ""
if OUT_FILE.exists():
with open(OUT_FILE, "r") as f:
previous_ip = f.read().strip()
if current_ip == previous_ip:
print(f"{time_msg()} no change IP={current_ip}")
return
else:
print(f"change IP from {previous_ip} to {current_ip}")
# Update DDNS
mssg = time_msg()
print(f"{mssg} access to value-domain")
url_set_ddns = (
f"https://dyn.value-domain.com/cgi-bin/dyn.fcg?"
f"d={MY_DOMAIN}&p={MY_PASS}&h={MY_HOSTNAME}"
)
try:
response = requests.get(url_set_ddns, timeout=10)
response.raise_for_status()
# Convert line breaks to spaces and combine consecutive spaces into one
result = ' '.join(response.text.strip().split())
except requests.RequestException as e:
print(f"{time_msg()} Failed to update DDNS: {e}")
return
mssg = time_msg()
print(f"{mssg} {MY_HOSTNAME}.{MY_DOMAIN} {result} IP={current_ip}")
# Save IP only if DDNS update is successful
if "status=0" in result:
with open(OUT_FILE, "w") as f:
f.write(current_ip)
print(f"{mssg} Successfully saved new IP: {current_ip}")
else:
print(f"{mssg} DDNS update failed, IP not saved")
if __name__ == "__main__":
main()
IP Address Log File Creation
# touch /tmp/ipadress
Run periodically
# crontab -e
* 00 * * * /usr/bin/python3 /var/www/system/ddnsset.py >> /var/log/ddns_updater.log 2>&1