Skip to main content
vagnerdtl
Explorer II
January 15, 2025
Solved

Hight SSL Negotiation time, when web filter Security profile has enable

Hey Guys

 

We are facing Hight SSL Negotiation time, when WEB filter profile has enable on the rule at Security Profile.

When we disable de WEB Filter profile on the rule, the SSL Time improve considerable .

To test i'm using this curl command, for google website. But this issue occur with any destination address

curl —resolve www.google.com.br:443:142.250.219.131 -w "DNS_resolution: %{time_namelookup}| TCP_negotiation_time: %{time_connect}| SSL_negotiation_time: %{time_appconnect}| TTFB: %{time_starttransfer}| Total time: %{time_total} \n" -o /dev/null -vsL https://www.google.com.br

When WEB Filter profille is enable the SSL_negotiation_time is more 3 seconds

When WEB Filter profile is disabled  the SSL_negotiation_time is not more tham milliseconds

 

When I check on System ==> Fortiguard  My Web Filter Status is average 123 ms.

 

Someone experienced this same issue ?

AEK
AEKAnswer
SuperUser
January 15, 2025

Hi Vagner

Please try these troubleshooting steps. I'm sure it will help you find the root cause.

https://community.fortinet.com/t5/FortiGate/Troubleshooting-Tip-FortiGuard-Web-Filtering-problems/ta-p/196965

Especially the diag debug part.

AEK

7 replies

adambomb1219
SuperUser
SuperUser
January 15, 2025

Are you decrypting that traffic?  

vagnerdtl
vagnerdtlAuthor
Explorer II
January 15, 2025

Hi

 

I'm not decrypting.

 

AEK
SuperUser
SuperUser
January 15, 2025

Hi Vagner

Under System > FortiGuard, try enable Web Filter cache then try "twice" and see if the second attempt has better performance.

AEK
vagnerdtl
vagnerdtlAuthor
Explorer II
January 15, 2025

Hi
It's already enabled with 60 minute

AEK
SuperUser
AEKAnswer
SuperUser
January 15, 2025

Hi Vagner

Please try these troubleshooting steps. I'm sure it will help you find the root cause.

https://community.fortinet.com/t5/FortiGate/Troubleshooting-Tip-FortiGuard-Web-Filtering-problems/ta-p/196965

Especially the diag debug part.

AEK
vagnerdtl
vagnerdtlAuthor
Explorer II
January 20, 2025

 

Hey AEK 


Thank you, this link drove me to solve the issue.
Additional i used that link as well


https://community.fortinet.com/t5/FortiGate/Technical-Tip-Configure-interface-for-IPS-TLS-protocol-active/ta-p/198382

I were able to check when i used diagnose command some probe has been failure and some doesn't. When Failure, there is High Latency. When not, doesn't

diagnose ips debug enable ssl
diagnose ips debug enable urlfilter
diagnose debug enable

[2877@-1]eng_debug_log: Connecting to x.y.v.z:443 (test.test.com.br)

[2877@-1]probe_finish: probe is finished. id: 1127353, sess: 4042465.  <<<<<<======= Probe Works Fine = low Latency

 

At second attempt I experienced Hight Latency more than 3 seconds on SSL connection, and like suggest document the Proble failed   

[2877@-1]eng_debug_log:   Server: x.y.v.z:443

[2877@-1]eng_debug_log:   Probe failed: unable to connect.  <<<<<<===== Proble Failure = High Latency


 So i used: 

diagnose debug rating
Like suggested the link that you send senthttps://community.fortinet.com/t5/FortiGate/Troubleshooting-Tip-FortiGuard-Web-Filtering-problems/ta-p/196965


So just 3 Fortinet Services address were reachable (Flag "D"), all others don't (Flag "F)

 

IP Weight RTT Flags TZ FortiGuard-requests Curr Lost Total Lost
12.34.97.71 20 127 DI -5 3714329 0 18578 W
208.184.237.61 50 184 D -8 32184 0 1344 W
173.243.138.91 60 178 D -8 56753 0 1244 W
140.174.22.72 20 0 F -5 170173 170173 170173
12.34.97.72 20 0 F -5 170173 170173 170173
140.174.22.73 20 0 F -5 170173 170173 170173
12.34.97.73 20 0 F -5 170173 170173 170173
12.34.97.74 20 0 F -5 170173 170173 170173
12.34.97.75 20 0 F -5 170173 170173 170173
140.174.22.71 20 0 F -5 170180 170180 170180
194.69.172.31 30 0 F 0 170173 170173 170173
194.69.172.32 30 0 F 0 170173 170173 170173
194.69.172.33 30 0 F 0 170173 170173 170173
209.40.106.91 30 0 F -6 31952 31952 31952
209.40.106.92 30 0 F -6 26192 26192 26192
83.231.212.85 40 0 F 1 170173 170173 170173
83.231.212.86 40 0 F 1 170173 170173 170173
83.231.212.84 40 0 F 1 170173 170173 170173
83.231.212.81 40 0 F 1 170173 170173 170173
83.231.212.82 40 0 F 1 170173 170173 170173
83.231.212.83 40 0 F 1 170173 170173 170173
173.243.138.92 50 0 F -8 170173 170173 170173
173.243.138.93 50 0 F -8 170173 170173 170173
208.184.237.62 50 0 F -8 170172 170172 170172
210.7.96.11 120 0 F 9 170172 170172 170172
210.7.96.12 120 0 F 9 170172 170172 170172
210.7.96.13 120 0 F 9 170172 170172 170172
210.7.96.14 120 0 F 9 170172 170172 170172

 

When i checked my route table, there were only static route (via internet interface) to the these three address that works. For other all there are no route.

That's reason some times works, some time doesnt.

Cause the Firewall use like a round robin feature do balance accross these all address. 

The solution, i have fixed my route table to reacher all these address via internet interface.
There is no flag "F".
IP Weight RTT Flags TZ FortiGuard-requests Curr Lost Total Lost Updated Time
12.34.97.74 20 124 -5 67715 0 15431 Mon 
12.34.97.72 20 127 -5 58611 0 15438 Mon 
12.34.97.73 20 127 -5 23151 0 15430 Mon 
12.34.97.71 20 127 DI -5 359512 0 3722 Mon 
140.174.22.73 20 131 -5 55354 0 15439 
140.174.22.71 20 135 -5 293970 0 15493 Mon 
140.174.22.72 20 135 -5 19964 0 15426 Mon 
12.34.97.75 20 136 -5 83878 0 15441 Mon 
209.40.106.91 30 142 -6 18312 0 15416 Mon 
209.40.106.94 30 142 -6 18311 0 15415 Mon
209.40.106.93 30 143 -6 18310 0 15414 Mon 
209.40.106.92 30 144 -6 18310 0 15414 Mon
194.69.172.32 30 201 0 18310 0 15414 Mon
194.69.172.33 30 205 0 18310 0 15414 Mon
194.69.172.31 30 206 0 18310 0 15414 Mon 
83.231.212.85 40 208 1 18311 0 15415 Mon 
83.231.212.82 40 208 1 18311 0 15415 Mon 
83.231.212.84 40 208 1 18310 0 15414 Mon 
83.231.212.86 40 210 1 18311 0 15415 Mon
83.231.212.83 40 211 1 18310 0 15414 Mon 
83.231.212.81 40 213 1 18310 0 15414 Mon 
173.243.138.91 50 175 D -8 8312 0 480 Mon 
173.243.138.93 50 177 -8 18311 0 15415 Mon 
173.243.138.92 50 177 -8 18310 0 15414 Mon 
208.184.237.62 50 185 -8 18310 0 15414 Mon 
208.184.237.61 50 186 D -8 7722 0 441 Mon 
210.7.96.13 120 272 9 18310 0 15414 Mon 
210.7.96.12 120 272 9 18310 0 15414 Mon 
210.7.96.14 120 274 9 18310 0 15414 Mon 
210.7.96.11 120 279 9 18311 0 15415 Mon 




 

AEK
SuperUser
SuperUser
January 20, 2025

Hi Vagner

Glad to see you were able to resolve the issue.

AEK
Thought Leadership. Security Summit. Thursday, November 12th, PGA National Resort, Palm Beach Gardens, FL.
Thought Leadership. Security Summit. Thursday, October 8th. Disney's Grand Californian Hotel & SPA, Anaheim, CA.
Security Operations Summit: Modernize SecOps. Operate AI-Native.AMER: November 4 | 9:00 AM PST. India and SAARC: November 5 | 10:00 AM IST. EMEA: November 5 | 10:30 AM CET. APAC: November 5 | 11:00 AM SGT