### Author:  [@plorenz](https://openziti.discourse.group/u/plorenz)
#### Post date: [December 7, 2023, 12:32am UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/21 "2023-12-07T00:32:39Z")
> [@dmuensterer](#):
>
> What **exactly** do you mean by that? Open TCP connections? Just trying to understand also what an application can do to prevent the problem.
I know one place we've seen it is with some load balancer software. I think maybe it was closing the connection but not sending a TCP FIN message, so tunneler was never notified that the connection was closed. @scareything will hopefully correct me if I've got the details wrong.
---
### Author:  [@dmuensterer](https://openziti.discourse.group/u/dmuensterer)
#### Post date: [December 7, 2023, 6:40pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/22 "2023-12-07T18:40:48Z")
I'm unsure why the amount of idle circuits happens. Using `tcpdump`, I can see that the connections are closed correctly via TCP FIN messages. Any ideas as to why this happens?
```auto
dmuensterer@bastion:~$ sudo tcpdump -i any port 10051
tcpdump: data link type LINUX_SLL2
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on any, link-type LINUX_SLL2 (Linux cooked v2), snapshot length 262144 bytes
19:35:03.268283 ziti0 Out IP bastion.45818 > 100.64.0.4.zabbix-trapper: Flags [S], seq 2908279969, win 64240, options [mss 1460,sackOK,TS val 2170538484 ecr 0,nop,wscale 7], length 0
19:35:03.277572 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.45818: Flags [S.], seq 396031900, ack 2908279970, win 65535, options [mss 32768,nop,wscale 14], length 0
19:35:03.277579 ziti0 Out IP bastion.45818 > 100.64.0.4.zabbix-trapper: Flags [.], ack 1, win 502, length 0
19:35:03.277608 ziti0 Out IP bastion.45818 > 100.64.0.4.zabbix-trapper: Flags [P.], seq 1:75, ack 1, win 502, length 74
19:35:03.285306 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.45818: Flags [.], seq 1:1461, ack 75, win 3, length 1460
19:35:03.285311 ziti0 Out IP bastion.45818 > 100.64.0.4.zabbix-trapper: Flags [.], ack 1461, win 501, length 0
19:35:03.285314 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.45818: Flags [.], seq 1461:2921, ack 75, win 3, length 1460
19:35:03.285316 ziti0 Out IP bastion.45818 > 100.64.0.4.zabbix-trapper: Flags [.], ack 2921, win 494, length 0
19:35:03.285318 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.45818: Flags [.], seq 2921:4381, ack 75, win 3, length 1460
19:35:03.285320 ziti0 Out IP bastion.45818 > 100.64.0.4.zabbix-trapper: Flags [.], ack 4381, win 485, length 0
19:35:03.285328 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.45818: Flags [P.], seq 4381:5509, ack 75, win 3, length 1128
19:35:03.285330 ziti0 Out IP bastion.45818 > 100.64.0.4.zabbix-trapper: Flags [.], ack 5509, win 477, length 0
19:35:03.285531 ziti0 Out IP bastion.45818 > 100.64.0.4.zabbix-trapper: Flags [F.], seq 75, ack 5509, win 501, length 0
19:35:03.285903 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.45818: Flags [.], ack 76, win 3, length 0
19:35:03.286031 ziti0 Out IP bastion.45832 > 100.64.0.4.zabbix-trapper: Flags [S], seq 1523320303, win 64240, options [mss 1460,sackOK,TS val 2170538502 ecr 0,nop,wscale 7], length 0
19:35:03.288265 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.45818: Flags [F.], seq 5509, ack 76, win 3, length 0
19:35:03.288269 ziti0 Out IP bastion.45818 > 100.64.0.4.zabbix-trapper: Flags [.], ack 5510, win 501, length 0
19:35:03.295162 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.45832: Flags [S.], seq 396128851, ack 1523320304, win 65535, options [mss 32768,nop,wscale 14], length 0
19:35:03.295168 ziti0 Out IP bastion.45832 > 100.64.0.4.zabbix-trapper: Flags [.], ack 1, win 502, length 0
19:35:03.295190 ziti0 Out IP bastion.45832 > 100.64.0.4.zabbix-trapper: Flags [P.], seq 1:259, ack 1, win 502, length 258
19:35:03.301504 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.45832: Flags [P.], seq 1:104, ack 259, win 3, length 103
19:35:03.301509 ziti0 Out IP bastion.45832 > 100.64.0.4.zabbix-trapper: Flags [.], ack 104, win 502, length 0
19:35:03.301526 ziti0 Out IP bastion.45832 > 100.64.0.4.zabbix-trapper: Flags [F.], seq 259, ack 104, win 502, length 0
19:35:03.301989 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.45832: Flags [.], ack 260, win 3, length 0
19:35:03.308321 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.45832: Flags [F.], seq 104, ack 260, win 3, length 0
19:35:03.308325 ziti0 Out IP bastion.45832 > 100.64.0.4.zabbix-trapper: Flags [.], ack 105, win 502, length 0
19:35:08.312165 ziti0 Out IP bastion.53790 > 100.64.0.4.zabbix-trapper: Flags [S], seq 3785237650, win 64240, options [mss 1460,sackOK,TS val 2170543528 ecr 0,nop,wscale 7], length 0
19:35:08.322980 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.53790: Flags [S.], seq 396225803, ack 3785237651, win 65535, options [mss 32768,nop,wscale 14], length 0
19:35:08.322988 ziti0 Out IP bastion.53790 > 100.64.0.4.zabbix-trapper: Flags [.], ack 1, win 502, length 0
19:35:08.323022 ziti0 Out IP bastion.53790 > 100.64.0.4.zabbix-trapper: Flags [.], seq 1:1461, ack 1, win 502, length 1460
19:35:08.323023 ziti0 Out IP bastion.53790 > 100.64.0.4.zabbix-trapper: Flags [P.], seq 1461:2921, ack 1, win 502, length 1460
19:35:08.323027 ziti0 Out IP bastion.53790 > 100.64.0.4.zabbix-trapper: Flags [.], seq 2921:4381, ack 1, win 502, length 1460
19:35:08.323028 ziti0 Out IP bastion.53790 > 100.64.0.4.zabbix-trapper: Flags [P.], seq 4381:5841, ack 1, win 502, length 1460
19:35:08.323029 ziti0 Out IP bastion.53790 > 100.64.0.4.zabbix-trapper: Flags [P.], seq 5841:6497, ack 1, win 502, length 656
19:35:08.323047 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.53790: Flags [.], ack 2921, win 3, length 0
19:35:08.323061 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.53790: Flags [.], ack 5841, win 3, length 0
19:35:08.334556 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.53790: Flags [P.], seq 1:106, ack 6497, win 3, length 105
19:35:08.334563 ziti0 Out IP bastion.53790 > 100.64.0.4.zabbix-trapper: Flags [.], ack 106, win 502, length 0
19:35:08.334593 ziti0 Out IP bastion.53790 > 100.64.0.4.zabbix-trapper: Flags [F.], seq 6497, ack 106, win 502, length 0
19:35:08.334627 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.53790: Flags [.], ack 6498, win 3, length 0
19:35:08.341659 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.53790: Flags [F.], seq 106, ack 6498, win 3, length 0
19:35:08.341668 ziti0 Out IP bastion.53790 > 100.64.0.4.zabbix-trapper: Flags [.], ack 107, win 502, length 0
19:35:33.338740 ziti0 Out IP bastion.42338 > 100.64.0.4.zabbix-trapper: Flags [S], seq 1821337844, win 64240, options [mss 1460,sackOK,TS val 2170568554 ecr 0,nop,wscale 7], length 0
19:35:33.348655 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.42338: Flags [S.], seq 396322755, ack 1821337845, win 65535, options [mss 32768,nop,wscale 14], length 0
19:35:33.348663 ziti0 Out IP bastion.42338 > 100.64.0.4.zabbix-trapper: Flags [.], ack 1, win 502, length 0
19:35:33.348743 ziti0 Out IP bastion.42338 > 100.64.0.4.zabbix-trapper: Flags [P.], seq 1:245, ack 1, win 502, length 244
19:35:33.355690 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.42338: Flags [P.], seq 1:104, ack 245, win 3, length 103
19:35:33.355695 ziti0 Out IP bastion.42338 > 100.64.0.4.zabbix-trapper: Flags [.], ack 104, win 502, length 0
19:35:33.355716 ziti0 Out IP bastion.42338 > 100.64.0.4.zabbix-trapper: Flags [F.], seq 245, ack 104, win 502, length 0
19:35:33.355735 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.42338: Flags [.], ack 246, win 3, length 0
19:35:33.362821 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.42338: Flags [F.], seq 104, ack 246, win 3, length 0
19:35:33.362825 ziti0 Out IP bastion.42338 > 100.64.0.4.zabbix-trapper: Flags [.], ack 105, win 502, length 0
19:36:03.360547 ziti0 Out IP bastion.42010 > 100.64.0.4.zabbix-trapper: Flags [S], seq 541629275, win 64240, options [mss 1460,sackOK,TS val 2170598576 ecr 0,nop,wscale 7], length 0
19:36:03.371208 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.42010: Flags [S.], seq 396419708, ack 541629276, win 65535, options [mss 32768,nop,wscale 14], length 0
19:36:03.371219 ziti0 Out IP bastion.42010 > 100.64.0.4.zabbix-trapper: Flags [.], ack 1, win 502, length 0
19:36:03.371258 ziti0 Out IP bastion.42010 > 100.64.0.4.zabbix-trapper: Flags [P.], seq 1:259, ack 1, win 502, length 258
19:36:03.377822 ziti0 In IP 100.64.0.4.zabbix-trapper > bastion.42010: Flags [P.], seq 1:104, ack 259, win 3, length 103
19:36:03.377828 ziti0 Out IP bastion.42010 > 100.64.0.4.zabbix-trapper: Flags [.], ack 104, win 502, length 0
19:36:03.377853 ziti0 Out IP bastion.42010 > 100.64.0.4.zabbix-trapper: Flags [F.], seq 259, ack 104, win 502, length 0
```
I'm really interested in why Ziti thinks those circuits should be kept open and what I can do to prevent this problem.
---
### Author:  [@plorenz](https://openziti.discourse.group/u/plorenz)
#### Post date: [December 7, 2023, 7:12pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/23 "2023-12-07T19:12:33Z")
Are you using ziti-edge-tunnel or an edge router/tunneler to intercept/host traffic? I'm hoping we can try a different client and see if we can narrow it down to a specific code base.
Let us know what you're using, and if you're willing to try a different tunneler to try and narrow things down.
Thank you,
Paul
---
### Author:  [@dmuensterer](https://openziti.discourse.group/u/dmuensterer)
#### Post date: [December 7, 2023, 7:15pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/24 "2023-12-07T19:15:48Z")
Thanks, I'm using `ziti-edge-tunnel` on both sides and of course I'd like to try a different tunneler to see if we can prevent the problem. Just tell me what I should try 🙂
---
### Author:  [@plorenz](https://openziti.discourse.group/u/plorenz)
#### Post date: [December 7, 2023, 7:47pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/25 "2023-12-07T19:47:58Z")
The simplest thing to try would be `ziti tunnel`. It's a standalone version of the tunneling code in the edge-router/tunneler. `ziti-edge-tunnel` is more full featured and lighter weight, so we don't generally recommend it, but in this case it should be a simple drop in replacement, at least if you're on linux.
If you can try `ziti tunnel tproxy -i ` , let me know how that works.
FYI, the per-service max idle time is almost done.Settings for tcp keepalives in intercept and host configs is up next. See:
- [Configurable Timer needed to close idle circuits · Issue #1496 · openziti/ziti · GitHub](https://github.com/openziti/ziti/issues/1496)
- [Add config option for tcp keep-alive in intercept.v1, host.v1 and host.v2 · Issue #1567 · openziti/ziti · GitHub](https://github.com/openziti/ziti/issues/1567)
Appreciate your helping tracking this down!
Paul
---
### Author:  [@dmuensterer](https://openziti.discourse.group/u/dmuensterer)
#### Post date: [December 7, 2023, 10:35pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/26 "2023-12-07T22:35:52Z")
> [@plorenz](#):
>
> The simplest thing to try would be `ziti tunnel`
On both the dial and bind side?
> [@plorenz](#):
>
> FYI, the per-service max idle time is almost done.Settings for tcp keepalives in intercept and host configs is up next
Very cool, I very much appreciate it! Thanks
---
### Author:  [@plorenz](https://openziti.discourse.group/u/plorenz)
#### Post date: [December 7, 2023, 10:44pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/27 "2023-12-07T22:44:33Z")
> [@dmuensterer](#):
>
> On both the dial and bind side?
Sure, let's start with that, and then we can try variations depending on the outcome of the first test.
---
### Author:  [@dmuensterer](https://openziti.discourse.group/u/dmuensterer)
#### Post date: [December 8, 2023, 12:44pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/28 "2023-12-08T12:44:25Z")
**Alrighty, running ziti tunnel on both `support.mycompany.ziti` (dial) and `zabbix.mycompany.ziti` (bind):**
```auto
ziti@zt:~/.ziti/quickstart/zt/ziti-bin$ ziti edge list identities "limit 100" | grep zabbix
│ fSBYXsTxXr │ support.mycompany.ziti │ Default │ ssh,zabbix_agent │ Default │
│ yBJ68BYIL │ zabbix.mycompany.ziti │ Default │ admin,bind_web80,ssh │ Default │
```
Now created the following service:
```auto
ziti edge create config "mycompanyAllowZabbixAgent10051-Server" "cea49285-6c07-42cf-9f52-09a9b115c783" {"hostname":"127.0.0.1","port":10051,"protocol":"tcp"}
ziti edge create config "mycompanyAllowZabbixAgent10051-Client" "f2dd2df0-9c04-4b84-a91e-71437ac229f1" {"hostname":"zabbix.mycompany.ziti","port":10051}
ziti edge create service "mycompany_Allow_Zabbix_Agent_10051" --configs [3bCieUa19ltK2Zy8WIoSbc, 7e1QFnfonj72kEbEvSssUL]
ziti edge create service-policy "mycompanyAllowZabbixAgent10051-BindPolicy" Bind --semantic AnyOf --serviceRoles [@5hGZLFMoqtAjKeOZmvbFIn] --identityRoles [@yBJ68BYIL]
ziti edge create service-policy "mycompanyAllowZabbixAgent10051-DialPolicy" Dial --semantic AnyOf --serviceRoles [@5hGZLFMoqtAjKeOZmvbFIn] --identityRoles [#zabbix_agent]
```
Network connection is possible:
```auto
dmuensterer@support:~$ echo "" > /dev/tcp/zabbix.mycompany.ziti/10051
dmuensterer@support:~$
```
No circuit there yet:
```auto
ziti@zt:~/.ziti/quickstart/zt/ziti-bin$ ziti fabric list circuits | grep "mycompany_Allow_Zabbix_Agent_10051" | wc -l
0
```
Let's start the `zabbix-agent` and check again:
```auto
ziti@zt:~/.ziti/quickstart/zt/ziti-bin$ ziti fabric list circuits | grep "mycompany_Allow_Zabbix_Agent_10051" | wc -l
0
```
Huh, still 0? The scheduled data transmission works though (approx. once a minute) - so looks like the circuit is created and closed immediately afterwards and there is no problem using `ziti tunnel` on both sides?
---
### Author:  [@dmuensterer](https://openziti.discourse.group/u/dmuensterer)
#### Post date: [December 8, 2023, 1:00pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/29 "2023-12-08T13:00:38Z")
**Running ziti tunnel `support.mycompany.ziti` (dial) and ziti-edge-tunnel on `zabbix.mycompany.ziti` (bind):**
```auto
ziti@zt:~/.ziti/quickstart/zt/ziti-bin$ ziti fabric list circuits | grep "mycompany_Allow_Zabbix_Agent_10051" | wc -l
0
```
Still 0.
**Running ziti-edge-tunnel on `support.mycompany.ziti` (dial) and ziti tunnel on `zabbix.mycompany.ziti` (bind):**
```auto
ziti@zt:~/.ziti/quickstart/zt/ziti-bin$ ziti fabric list circuits | grep "mycompany_Allow_Zabbix_Agent_10051" | wc -l
0
```
Still 0.
**Running ziti-edge-tunnel `support.mycompany.ziti` (dial) and ziti-edge-tunnel on `zabbix.mycompany.ziti` (bind):**
```auto
ziti@zt:~/.ziti/quickstart/zt/ziti-bin$ date
Fri Dec 8 13:55:39 CET 2023
ziti@zt:~/.ziti/quickstart/zt/ziti-bin$ ziti fabric list circuits | grep "mycompany_Allow_Zabbix_Agent_10051" | wc -l
4
```
let's wait 5 minutes:
```auto
ziti@zt:~/.ziti/quickstart/zt/ziti-bin$ date
Fri Dec 8 14:00:03 CET 2023
ziti@zt:~/.ziti/quickstart/zt/ziti-bin$ ziti fabric list circuits | grep "mycompany_Allow_Zabbix_Agent_10051" | wc -l
20
```
Aha! Looks like we found that the problem only occurs with `ziti-edge-tunnel` on both sides?
If it helps, I can provide a 5 minute PCAP of the traffic that's sent over the tunneler?
---
### Author:  [@plorenz](https://openziti.discourse.group/u/plorenz)
#### Post date: [December 8, 2023, 2:47pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/30 "2023-12-08T14:47:37Z")
> [@dmuensterer](#):
>
> Aha! Looks like we found that the problem only occurs with `ziti-edge-tunnel` on both sides?
>
> If it helps, I can provide a 5 minute PCAP of the traffic that's sent over the tunneler?
This is out of my area of expertise, so I've asked the folks who work on ziti-edge-tunnel to take a look and hop on this thread. I know I'm repeating myself, but we really appreciate you helping us track this down!
---
### Author:  [@ekoby](https://openziti.discourse.group/u/ekoby)
#### Post date: [December 8, 2023, 3:15pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/31 "2023-12-08T15:15:52Z")
any chance you are willing to try the following setups:
- ziti-tunnel -\> ziti-edge-tunnel
- ziti-edge-tunnel -\> ziti-tunnel
and report your finding?
that would really help finding the culprit. also when you see idle circuit can you check connections on the terminating side with `netstat`? maybe tcpdump on the terminating side as well
edit:
Sorry, I just noticed you already did that
---
### Author:  [@ekoby](https://openziti.discourse.group/u/ekoby)
#### Post date: [December 8, 2023, 8:41pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/32 "2023-12-08T20:41:11Z")
is there any chance we can get packet capture on the terminating side -- behind hosting ziti-edge-tunnel?
just filtered to ziti-edge-tunnel to the service if possible
---
### Author:  [@dmuensterer](https://openziti.discourse.group/u/dmuensterer)
#### Post date: [December 8, 2023, 9:30pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/33 "2023-12-08T21:30:46Z")
> [@ekoby](#):
>
> is there any chance we can get packet capture on the terminating side -- behind hosting ziti-edge-tunnel?
> just filtered to ziti-edge-tunnel to the service if possible
Absolutely. Any email address to where I can send the pcap?
---
### Author:  [@scareything](https://openziti.discourse.group/u/scareything)
#### Post date: [December 8, 2023, 9:51pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/34 "2023-12-08T21:51:39Z")
I'm not sure if you've figured this out yet but just to be sure: you can DM to @ekoby on this discourse group if you click on his avatar:
---
### Author:  [@dmuensterer](https://openziti.discourse.group/u/dmuensterer)
#### Post date: [December 8, 2023, 11:22pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/35 "2023-12-08T23:22:09Z")
@ekoby I've sent you the packet capture via DM.
> [@ekoby](#):
>
> when you see idle circuit can you check connections on the terminating side with `netstat`?
Sure, here's the output:
```auto
dmuensterer@zabbix:~$ netstat
Active Internet connections (w/o servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 localhos:zabbix-trapper localhost:46502 TIME_WAIT
tcp 0 0 localhos:zabbix-trapper localhost:51674 TIME_WAIT
tcp 0 0 localhost:ssh localhost:42688 ESTABLISHED
tcp 0 36 localhost:42688 localhost:ssh ESTABLISHED
tcp 0 0 localhost:55752 localhost:http ESTABLISHED
tcp 0 0 localhos:zabbix-trapper localhost:47748 TIME_WAIT
tcp 0 0 localhos:zabbix-trapper localhost:51670 TIME_WAIT
tcp 0 0 zabbix:45796 zt-router-1.mycomp:8442 ESTABLISHED
tcp 0 0 zabbix:36682 zt.mycompany.de:8442 ESTABLISHED
tcp 0 0 localhos:zabbix-trapper localhost:52954 TIME_WAIT
tcp 0 0 localhos:zabbix-trapper localhost:47750 TIME_WAIT
tcp6 0 0 127.0.0.1:33154 127.0.0.1:5355 TIME_WAIT
tcp6 0 0 127.0.0.1:44454 127.0.0.1:5355 TIME_WAIT
```
---
### Author:  [@dmuensterer](https://openziti.discourse.group/u/dmuensterer)
#### Post date: [December 18, 2023, 11:36pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/36 "2023-12-18T23:36:22Z")
Hi, were you already able to find anything?
I'd love to use Ziti with Zabbix but it looks like it's currently not possible?
---
### Author:  [@ekoby](https://openziti.discourse.group/u/ekoby)
#### Post date: [December 19, 2023, 1:06am UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/37 "2023-12-19T01:06:58Z")
A [new release](https://github.com/openziti/ziti-tunnel-sdk-c/releases/tag/v0.22.18) of ziti-edge-tunnel was just released today.
One of the changes was to enable TCP keep alive on connections from hosting ZET. This should cleanup abandoned TCP connections fairly quickly.
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### Author:  [@dmuensterer](https://openziti.discourse.group/u/dmuensterer)
#### Post date: [December 19, 2023, 9:24am UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/38 "2023-12-19T09:24:13Z")
Thanks! I’ll test the new release and report back if the problem was solved!
I just had a very quick look at the commit and it looks like there’s nothing I need to configure here additionally for it to work?
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### Author:  [@ekoby](https://openziti.discourse.group/u/ekoby)
#### Post date: [December 19, 2023, 12:02pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/39 "2023-12-19T12:02:32Z")
Correct, just drop in the new version and give it a go
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### Author:  [@dmuensterer](https://openziti.discourse.group/u/dmuensterer)
#### Post date: [December 19, 2023, 2:20pm UTC](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817/40 "2023-12-19T14:20:23Z")
Thanks. I've deployed v0.22.18 on both the Dial and Bind side, but unfortunately the amount of idling circuits still rises continuously:
[Previous page](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817.md?page=1)
[Next page](https://openziti.discourse.group/t/fabric-crashes-with-thousands-of-circuits-and-idle-threshold-warnings/1817.md?page=3)