# \[WP760x\]\[SW\] Watch Dog Timer for native Linux **URL:** \ **Category:** Legato Linux distribution (Yocto project)\ **Created:** [November 19, 2019, 4:38am UTC](https://forum.legato.io/t/wp760x-sw-watch-dog-timer-for-native-linux/4846 "2019-11-19T04:38:52Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![HIROKI11976](https://avatars.discourse-cdn.com/v4/letter/h/a9adbd/32.png) [@HIROKI11976](https://forum.legato.io/u/HIROKI11976)\ **Post date:** [November 19, 2019, 4:38am UTC](https://forum.legato.io/t/wp760x-sw-watch-dog-timer-for-native-linux/4846/1 "2019-11-19T04:38:52Z")
Question: Does WP760x have Watch Dog Time for native Linux? Back Ground: Generally, native Linux have WDT under /dev/watchdog. So we would like to know whether WP760x have such WDT. ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.legato.io/jyijyi/32/822_2.png) [@jyijyi](https://forum.legato.io/u/jyijyi)\ **Post date:** [November 19, 2019, 9:51am UTC](https://forum.legato.io/t/wp760x-sw-watch-dog-timer-for-native-linux/4846/2 "2019-11-19T09:51:40Z")
No, I don’t see there is /dev/watchdog. Please use the legato watchdog API. > **[Watchdog Service - Legato Docs](https://docs.legato.io/latest/c_wdog.html)** > > legato™ is an open source Linux-based embedded platform designed to simplify connected IoT application development > **[Application Definition .adef - Legato Docs](https://docs.legato.io/latest/defFilesAdef.html#defFilesAdef_processwatchdogAction)** > > legato™ is an open source Linux-based embedded platform designed to simplify connected IoT application development ---
**Author:** ![HIROKI11976](https://avatars.discourse-cdn.com/v4/letter/h/a9adbd/32.png) [@HIROKI11976](https://forum.legato.io/u/HIROKI11976)\ **Post date:** [December 12, 2019, 11:32pm UTC](https://forum.legato.io/t/wp760x-sw-watch-dog-timer-for-native-linux/4846/3 "2019-12-12T23:32:21Z")
Hi, jyijyi I have an additional question about watchdog API. Question: Does watchdog legato API work either Software watchdog or Hardware watchdog? Back Ground: If Linux distribution is freeze, I would like to know whether watchdog legato API can be worked in this case. ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.legato.io/jyijyi/32/822_2.png) [@jyijyi](https://forum.legato.io/u/jyijyi)\ **Post date:** [December 13, 2019, 1:47am UTC](https://forum.legato.io/t/wp760x-sw-watch-dog-timer-for-native-linux/4846/4 "2019-12-13T01:47:45Z")
> **[Runtime Architecture - Legato Docs](https://docs.legato.io/latest/conceptsRuntimeArch.html)** > > legato™ is an open source Linux-based embedded platform designed to simplify connected IoT application development It says " The daemon monitors app’s processes for hangs or freezing and if the process doesn’t “kick” the watchdog daemon in a specified time (the default is **30**** seconds** ), the watchdog signals the Supervisor to perform a specified action. That means the reboot action is done by supervisor. ---
**Author:** ![HIROKI11976](https://avatars.discourse-cdn.com/v4/letter/h/a9adbd/32.png) [@HIROKI11976](https://forum.legato.io/u/HIROKI11976)\ **Post date:** [December 15, 2019, 4:12am UTC](https://forum.legato.io/t/wp760x-sw-watch-dog-timer-for-native-linux/4846/5 "2019-12-15T04:12:05Z")
Hi, jyijyi If “Legato” system was freeze, it seems that legato API watchdog can be worked to operate the specific process to Supervisor. However I would like to know whether WP can be worked watchdog if “Yocto distribution” was freeze. I think legato API watchdog could not be covered in the case of freezing Yocto distribution. I considered whether our system add external watchdog, that’s why I asked it. ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.legato.io/jyijyi/32/822_2.png) [@jyijyi](https://forum.legato.io/u/jyijyi)\ **Post date:** [December 16, 2019, 5:24am UTC](https://forum.legato.io/t/wp760x-sw-watch-dog-timer-for-native-linux/4846/6 "2019-12-16T05:24:02Z")
From here, it says the supervisor is run on legato system: > **[startlegato - Legato Docs](https://docs.legato.io/latest/toolsHost_startlegato.html)** > > legato™ is an open source Linux-based embedded platform designed to simplify connected IoT application development BTW, when you say yocto freezes, how can we simulate this situation ? ---
**Author:** ![HIROKI11976](https://avatars.discourse-cdn.com/v4/letter/h/a9adbd/32.png) [@HIROKI11976](https://forum.legato.io/u/HIROKI11976)\ **Post date:** [December 16, 2019, 5:45am UTC](https://forum.legato.io/t/wp760x-sw-watch-dog-timer-for-native-linux/4846/7 "2019-12-16T05:45:27Z")
Hi, jyijyi [https://partnercommunity.sierrawireless.com/s/case/5001M00001PGMDrQAP/00935522-wp7605hw-behavior-of-application-core-if-telecom-core-is-hangup](https://partnercommunity.sierrawireless.com/s/case/5001M00001PGMDrQAP/00935522-wp7605hw-behavior-of-application-core-if-telecom-core-is-hangup) (Sorry this is SFDC for only our account) According to the above SFDC, you said that module was reboot both telecom core and modem core if the module was hang-up. I think the recovery sequence of legato and yocto distribution in that case. “Yocto freezes” means to be supposed such module hang-up situation. I would like to know which areas inside of WP can be recovered automatically and whether legato API watch is worked in this module hang-up situation. ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.legato.io/jyijyi/32/822_2.png) [@jyijyi](https://forum.legato.io/u/jyijyi)\ **Post date:** [December 16, 2019, 6:37am UTC](https://forum.legato.io/t/wp760x-sw-watch-dog-timer-for-native-linux/4846/8 "2019-12-16T06:37:09Z")
I just have a look on the AT command user guide, there is a command AT!MCUWATCHDOG which is using the on-board MCU watchdog. It seems we already have a hardware watchdog there. Please create another SF ticket so that we will double confirm internally. BTW, are you asking about WP7605 only? I just check product technical specification, WP7605 belongs to Group B variants which do not have MCU. But other variants WP7601, WP7603, WP7607, WP7608, WP7609, there is on-board MCU. ---
**Author:** ![HIROKI11976](https://avatars.discourse-cdn.com/v4/letter/h/a9adbd/32.png) [@HIROKI11976](https://forum.legato.io/u/HIROKI11976)\ **Post date:** [December 16, 2019, 8:40am UTC](https://forum.legato.io/t/wp760x-sw-watch-dog-timer-for-native-linux/4846/9 "2019-12-16T08:40:30Z")
Hi, jyijyi I issued SFDC#00945564, please check it.