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[IDP Series] NIC Bypass

The Internal NICBypass helps prevent network outage due to IDP entering a hang state or experiencing high CPU utilization when the IDP device is in inline mode (transparent mode only). The internal NICBypass employs WatchDog Timers to achieve the functionality. The nicBypass script which is located in /usr/idp/device/bin/ prevents the interfaces from going into bypass mode when the IDP is working normally by resetting the watchdog timer. It also restores the interfaces to normal mode if they had gone into Bypass mode. The nicBypass script performs this check and takes the action (if required) every "loopInterval" seconds (the script 'sleeps' for "loopInterval" seconds).  These two parameters can be configured via the idp.cfg file on the IDP Sensor as shown below:                                                                                                                nicBypass.watchdogInterval             10 (secs)  nicBypass.loopInt
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[ScreenOS] Snoop and debug flow

Debug flow basic: Understanding debug flow filters: https://kb.juniper.net/InfoCenter/index?page=content&id=KB6709&actp=METADATA Running "debug flow basic": https://kb.juniper.net/InfoCenter/index?page=content&id=KB12208 How do I capture debugging (debug flow) information?: https://kb.juniper.net/InfoCenter/index?page=content&id=KB5536&actp=METADATA When to use 'snoop' and 'debug flow': https://kb.juniper.net/InfoCenter/index?page=content&id=KB5967&actp=METADATA Snoop: How do you use Snoop for troubleshooting?:https://kb.juniper.net/InfoCenter/index?page=content&id=KB5411&actp=METADATA What options are available when configuring snoop?: https://kb.juniper.net/InfoCenter/index?page=content&id=KB6586&actp=METADATA How to apply the logical 'AND' or 'OR' snoop filters: https://kb.juniper.net/InfoCenter/index?page=content&id=KB6707&actp=METADATA How do I interpret the snoop out
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[vSRX] Installing on KVM

Two ways VirtManager(GUI) virt install (cli) Other ways (Qemu) On Server: uname -a lscpu (architecture, support virtualization (VT-X), NUMA) lspci / lspci -vvv |grep Ether dmidecode lsmod | grep kvm virsh - qemu:///system list virsh dumpxml <instance ID> (will show configuration file for the VM, similar to .vmx file in vmware) virsh net-list --all virsh domiflist <vm-name> brctl show
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[ScreenOS] Firmware upgrade

screenos upgrade:  Please find the upgrade process below to upgrade remaining firewalls (if boot loader and image key are proper there is no need to update them)  1.       Upgrade the image key >> GUI access or Console + TFTP access is required.  2.       Upgrade the OS >> CLI+TFTP access is required.  3.       Upgrade the Boot loader >> Console + TFTP access required.  The firewall is in cluster, to upgrade the backup unit first you will need manage-ip configured on it.  Points to check before upgrading firewall:  ++ Please check nsrp status ‘get nsrp’. There should be a master and a primary backup (PB) available.  ++ Check the sessions on master and backup ‘get session info’ à this will ensure that session synchronization is happening properly.  ++ Check the routes on both the firewalls and they should be identical.  ++ Check whether both firewalls are in sync ‘exec nsrp sync globacl checksum’  ++ All above checks are done whether backup firewall is
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What is vSRX?

vSRX is a virtual firewall appliance for cloud environments. It runs as a VM on Hypervisors hosted on x86 hardware. It is built on Juniper's OS (JunOS), however unlike FreeBSD linux used by JunOS earlier, vSRX is developed on top of Yocto Linux (WindRiver). This allows the appliance to perform better than any other Virtual Firewall in the market. vSRX includes below features: 1. Full Stateful Firewall 2. Routing 3. VPN 4. IPS (Intrusion Detection and Prevention) 5. Application Firewall 6. Antivirus 7. AntiSpam 8. Webfiltering 9. Content-filtering 10. High Availability
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