# TCL errors

**URL:** <https://community.f5.com/t/tcl-errors/73966>\
**Category:** Technical Forums\
**Tags:** application-delivery\
**Created:** [February 9, 2024, 12:17am UTC](https://community.f5.com/t/tcl-errors/73966 "2024-02-09T00:17:11Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![adick](https://avatars.discourse-cdn.com/v4/letter/a/4af34b/32.png) [@adick](https://community.f5.com/u/adick)\
**Post date:** [February 9, 2024, 12:17am UTC](https://community.f5.com/t/tcl-errors/73966/1 "2024-02-09T00:17:11Z")

</div>

Hey Team,

We are experiencing some TCL errors with one of our iRules.

I didn’t build the iRule, but have inherited it from a past engineer, so I don’t have a ton of knowledge on the specifics, but I’m wondering if it is something we can discover a fix for:

Error:

partition1/F5\_L4\_TCP\_IPFIX

Feb &nbsp;8 13:52:18 [DN-DC3-LTM-02.domainname.com](http://DN-DC3-LTM-02.domainname.com) err tmm5[13713]: 01220001:3: TCL error: /partition1/F5\_L4\_TCP\_IPFIX \<CLIENT\_CLOSED\> - can’t read “rule1\_msg1”: no such variable &nbsp; &nbsp; while executing “IPFIX::msg set $rule1\_msg1 postOctetTotalCount [IP::stats bytes in]”  
Feb &nbsp;8 13:52:19 [DN-DC3-LTM-02.domainname.com](http://DN-DC3-LTM-02.domainname.com) err tmm4[13713]: 01220001:3: TCL error: /partition1/F5\_L4\_TCP\_IPFIX \<SERVER\_CLOSED\> - can’t read “rule1\_msg1”: no such variable &nbsp; &nbsp; while executing “IPFIX::msg set $rule1\_msg1 octetTotalCount [IP::stats bytes out]”  
Feb &nbsp;8 13:52:19 [DN-DC3-LTM-02.domainname.com](http://DN-DC3-LTM-02.domainname.com) err tmm4[13713]: 01220001:3: TCL error: /partition1/F5\_L4\_TCP\_IPFIX \<CLIENT\_CLOSED\> - can’t read “rule1\_msg1”: no such variable &nbsp; &nbsp; while executing “IPFIX::msg set $rule1\_msg1 postOctetTotalCount [IP::stats bytes in]”  
Feb &nbsp;8 13:52:19 [DN-DC3-LTM-02.domainname.com](http://DN-DC3-LTM-02.domainname.com) err tmm5[13713]: 01220001:3: TCL error: /partition1/F5\_L4\_TCP\_IPFIX \<SERVER\_CLOSED\> - can’t read “rule1\_msg1”: no such variable &nbsp; &nbsp; while executing “IPFIX::msg set $rule1\_msg1 octetTotalCount [IP::stats bytes out]”  
Feb &nbsp;8 13:52:19 [DN-DC3-LTM-02.domainname.com](http://DN-DC3-LTM-02.domainname.com) err tmm5[13713]: 01220001:3: TCL error: /partition1/F5\_L4\_TCP\_IPFIX \<CLIENT\_CLOSED\> - can’t read “rule1\_msg1”: no such variable &nbsp; &nbsp; while executing “IPFIX::msg set $rule1\_msg1 postOctetTotalCount [IP::stats bytes in]”  
Feb &nbsp;8 13:52:20 [DN-DC3-LTM-02.domainname.com](http://DN-DC3-LTM-02.domainname.com) err tmm3[13713]: 01220001:3: TCL error: /partition1/F5\_L4\_TCP\_IPFIX \<SERVER\_CLOSED\> - can’t read “rule1\_msg1”: no such variable &nbsp; &nbsp; while executing “IPFIX::msg set $rule1\_msg1 octetTotalCount [IP::stats bytes out]”  
Feb &nbsp;8 13:52:20 [DN-DC3-LTM-02.domainname.com](http://DN-DC3-LTM-02.domainname.com) err tmm3[13713]: 01220001:3: TCL error: /partition1/F5\_L4\_TCP\_IPFIX \<CLIENT\_CLOSED\> - can’t read “rule1\_msg1”: no such variable &nbsp; &nbsp; while executing “IPFIX::msg set $rule1\_msg1 postOctetTotalCount [IP::stats bytes in]”  
[user@DN-DC3-LTM-02:Active:In Sync] log #  
[user@DN-DC3-LTM-02:Active:In Sync] log #

IRULE:

when RULE\_INIT {&nbsp; set static::http\_rule1\_dest “”&nbsp; set static::http\_rule1\_tmplt “”}&nbsp;&nbsp;# CLIENT\_ACCEPTED event to initiate IPFIX destination and templatewhen CLIENT\_ACCEPTED {&nbsp; set start [clock clicks -milliseconds]&nbsp; if { $static::http\_rule1\_dest == “”} {&nbsp; &nbsp; # open the logging destination if it has not been opened yet&nbsp; &nbsp; set static::http\_rule1\_dest [IPFIX::destination open -publisher /western-hemisphere/IPFIX-PUB1]&nbsp; }&nbsp; if { $static::http\_rule1\_tmplt == “”} {&nbsp; &nbsp; # if the template has not been created yet, create the template&nbsp; &nbsp; set static::http\_rule1\_tmplt [IPFIX::template create “flowStartMilliseconds \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; sourceIPv4Address \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; sourceIPv6Address&nbsp; \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; destinationIPv4Address \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; destinationIPv6Address&nbsp; \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; sourceTransportPort \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; destinationTransportPort \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; protocolIdentifier \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; octetTotalCount \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; packetTotalCount \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; octetDeltaCount \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; packetDeltaCount \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; postNATSourceIPv4Address \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; postNATSourceIPv6Address&nbsp; \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; postNATDestinationIPv4Address \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; postNATDestinationIPv6Address&nbsp; \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; postNAPTSourceTransportPort \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; postNAPTDestinationTransportPort \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; postOctetTotalCount \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; postPacketTotalCount \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; postOctetDeltaCount \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; postPacketDeltaCount \&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; flowEndMilliseconds”]&nbsp; }}&nbsp;&nbsp;# SERVER\_CONNECTED event to initiate flow data to Tetration and populate 5 tupleswhen SERVER\_CONNECTED {&nbsp; set rule1\_msg1 [IPFIX::msg create $static::http\_rule1\_tmplt]&nbsp; set client\_closed\_flag 0&nbsp; set server\_closed\_flag 0&nbsp; IPFIX::msg set $rule1\_msg1 flowStartMilliseconds $start&nbsp; IPFIX::msg set $rule1\_msg1 protocolIdentifier [IP::protocol]&nbsp;&nbsp; # Clientside&nbsp; if { [clientside {IP::version}] equals “4” } {&nbsp; &nbsp; # Client IPv4 address&nbsp; &nbsp; IPFIX::msg set $rule1\_msg1 sourceIPv4Address [IP::client\_addr]&nbsp; &nbsp; # BIG-IP IPv4 VIP address&nbsp; &nbsp; IPFIX::msg set $rule1\_msg1 destinationIPv4Address [clientside {IP::local\_addr}]&nbsp; } else {&nbsp; &nbsp; # Client IPv6 address&nbsp; &nbsp; IPFIX::msg set $rule1\_msg1 sourceIPv6Address [IP::client\_addr]&nbsp; &nbsp; # BIG-IP IPv6 VIP address&nbsp; &nbsp; IPFIX::msg set $rule1\_msg1 destinationIPv6Address [clientside {IP::local\_addr}]&nbsp; }&nbsp; # Client port&nbsp; IPFIX::msg set $rule1\_msg1 sourceTransportPort [TCP::client\_port]&nbsp; # BIG-IP VIP port&nbsp; IPFIX::msg set $rule1\_msg1 destinationTransportPort [clientside {TCP::local\_port}]&nbsp;&nbsp;&nbsp; # Serverside&nbsp; if { [serverside {IP::version}] equals “4” } {&nbsp; &nbsp; # BIG-IP IPv4 self IP address&nbsp; &nbsp; IPFIX::msg set $rule1\_msg1 postNATSourceIPv4Address [IP::local\_addr]&nbsp; &nbsp; # Server IPv4 IP address&nbsp; &nbsp; IPFIX::msg set $rule1\_msg1 postNATDestinationIPv4Address [IP::server\_addr]&nbsp; } else {&nbsp; &nbsp; # BIG-IP IPv6 self IP address&nbsp; &nbsp; IPFIX::msg set $rule1\_msg1 postNATSourceIPv6Address [IP::local\_addr]&nbsp; &nbsp; # Server IPv6 IP address&nbsp; &nbsp; IPFIX::msg set $rule1\_msg1 postNATDestinationIPv6Address [IP::server\_addr]&nbsp; }&nbsp; # BIG-IP self IP port&nbsp; IPFIX::msg set $rule1\_msg1 postNAPTSourceTransportPort [TCP::local\_port]&nbsp; # Server port&nbsp; IPFIX::msg set $rule1\_msg1 postNAPTDestinationTransportPort [TCP::server\_port]}&nbsp;# SERVER\_CLOSED event to collect IP pkts and bytes count on serversidewhen SERVER\_CLOSED {&nbsp; set server\_closed\_flag 1&nbsp; # when flow is completed, BIG-IP to server REQUEST pkts and bytes count&nbsp; IPFIX::msg set $rule1\_msg1 octetTotalCount [IP::stats bytes out]&nbsp; IPFIX::msg set $rule1\_msg1 packetTotalCount [IP::stats pkts out]&nbsp; # when flow is completed, server to BIG-IP RESPONSE pkts and bytes count&nbsp;&nbsp; IPFIX::msg set $rule1\_msg1 octetDeltaCount [IP::stats bytes in]&nbsp; IPFIX::msg set $rule1\_msg1 packetDeltaCount [IP::stats pkts in]&nbsp; if { $client\_closed\_flag == 1} {&nbsp; &nbsp; # send the IPFIX log&nbsp; &nbsp; IPFIX::destination send $static::http\_rule1\_dest $rule1\_msg1&nbsp; }}&nbsp;&nbsp;# CLIENT\_CLOSED event to collect IP pkts and bytes count on clientsidewhen CLIENT\_CLOSED {&nbsp; set client\_closed\_flag 1&nbsp; # when flow is completed, client to BIG-IP REQUEST pkts and bytes octetDeltaCount&nbsp; IPFIX::msg set $rule1\_msg1 postOctetTotalCount [IP::stats bytes in]&nbsp; IPFIX::msg set $rule1\_msg1 postPacketTotalCount [IP::stats pkts in]&nbsp; # when flow is completed, BIG-IP to client RESPONSE pkts and bytes count&nbsp; IPFIX::msg set $rule1\_msg1 postOctetDeltaCount [IP::stats bytes out]&nbsp; IPFIX::msg set $rule1\_msg1 postPacketDeltaCount [IP::stats pkts out]&nbsp; # record the client closed time in ms&nbsp; IPFIX::msg set $rule1\_msg1 flowEndMilliseconds [clock click -milliseconds]&nbsp; if { $server\_closed\_flag == 1} {&nbsp; &nbsp; # send the IPFIX log&nbsp; &nbsp; IPFIX::destination send $static::http\_rule1\_dest $rule1\_msg1&nbsp; }}

---

<div class="post-metadata">

**Author:** ![KeesvandenBos](https://avatars.discourse-cdn.com/v4/letter/k/ecb155/32.png) [@KeesvandenBos](https://community.f5.com/u/KeesvandenBos)\
**Post date:** [February 9, 2024, 4:52pm UTC](https://community.f5.com/t/tcl-errors/73966/2 "2024-02-09T16:52:54Z")

</div>

Hi,

The error occurs when the rule1\_msg1 variable is empty.  
This could happen if a client doesn’t complete the 3way handshake and send a reset. Then the CLIENT\_CLOSE event is hit without the client sending any data, leaving rule1\_msg1 being never created in the other events.

Maybe you can solve this by adding this line in the when RULE\_INIT { section

```tcl
when RULE_INIT <span class="token punctuation">{</span>
    <span class="token keyword">set</span> <span class="token variable">static::http_rule1_dest</span> <span class="token string">""</span>
    <span class="token keyword">set</span> <span class="token variable">static::http_rule1_tmplt</span> <span class="token string">""</span>
    <span class="token keyword">set</span> <span class="token variable">rule1_msg1</span> <span class="token string">""</span>
<span class="token punctuation">}</span>

```

Hope it helps.

Cheers,

Kees

---

<div class="post-metadata">

**Author:** ![adick](https://avatars.discourse-cdn.com/v4/letter/a/4af34b/32.png) [@adick](https://community.f5.com/u/adick)\
**Post date:** [February 9, 2024, 10:25pm UTC](https://community.f5.com/t/tcl-errors/73966/3 "2024-02-09T22:25:54Z")

</div>

Thanks Kees!

This seems to be a good solution.

Could there be other reasons the CLIENT\_CLOSE event could get hit without the client sending data?&nbsp; I’m wondering if this iRule could be causing any problems with the VIPs that it is configured on?&nbsp; I heard from someone when you see TCL errors it usually means the VIP communication was cut off early.

Or if because it only triggers on CLIENT\_CLOSE maybe it is something where the client already had problems communicating and this is just the error that triggers when there is another issue present.

Thanks

---

<div class="post-metadata">

**Author:** ![F5\_Design\_Engineer](https://d1p9zq3aats0t8.cloudfront.net/user_avatar/community.f5.com/f5_design_engineer/32/2479_2.png) [@F5\_Design\_Engineer](https://community.f5.com/u/F5_Design_Engineer)\
**Post date:** [February 10, 2024, 3:23am UTC](https://community.f5.com/t/tcl-errors/73966/4 "2024-02-10T03:23:13Z")

</div>

Hi Adick,

There are many TCL online editors that you can check your code, you can make changes and execute till you find the desired results.

> **[Tcl Online Compiler](https://onecompiler.com/tcl/423z8u753)**
>
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> **[Online Programming Compilers and Editors](https://www.tutorialspoint.com/compilers/online-tcl-compiler.htm)**
>
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>
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 ![image_327668.png](https://d20hrnpixdzcsd.cloudfront.net/original/2X/9/9532d5fe6fa04fe16a12ab238dd2072bcc067912.png)

> **[Tcl Online Compiler](https://onecompiler.com/tcl/423z8u753)**
>
> OneCompiler's Tcl online editor helps you to write, compile, debug and run Tcl code online.

 ![image_327668.png](https://d20hrnpixdzcsd.cloudfront.net/original/2X/8/8b0933727d66fe698a6b8d223f5125f3e5489002.png)

 ![image_327668.png](https://d20hrnpixdzcsd.cloudfront.net/original/2X/b/b94571346498c4f6bf8e630a650f3db33dc6fbe4.png)

> **[Online Programming Compilers and Editors](https://www.tutorialspoint.com/compilers/online-tcl-compiler.htm)**
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> **[Free Online Tcl Compiler & Editor](https://www.jdoodle.com/execute-tcl-online)**
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Hope this Helps.

🙏

---

<div class="post-metadata">

**Author:** ![KeesvandenBos](https://avatars.discourse-cdn.com/v4/letter/k/ecb155/32.png) [@KeesvandenBos](https://community.f5.com/u/KeesvandenBos)\
**Post date:** [February 11, 2024, 10:04am UTC](https://community.f5.com/t/tcl-errors/73966/5 "2024-02-11T10:04:21Z")

</div>

Your welcome.

CLIENT\_CLOSED events gets triggers by the client ending the connection. And yes it is true, any TCL error will cause the Virtual Server to stop processing traffic.

rule1\_msg1 not being filled with data (and causing the TCL error) will only happen if a client doesn’t send any data after the connection has been created, same for SERVER\_CLOSED TCL error. If this irule is attached to a virtual server without a proxy profile (L7 connection) the BIG-IP will create the server connection the moment thhttps://my.f5.com/manage/s/article/K8082e client connection is completed. If the client doesn’t send any data, in the end the pool member will close its connection with the BIG-IP.  
[K8082](https://my.f5.com/manage/s/article/K8082) explains the differences between virtual server types.

It could be a client issue causing these erros’ Still it is better to first create an empty variable to make sure you do not run into issues.

Cheers,  
Kees