The analyst firm said that it issued the warning because it believes that Symantec is moving away from selling network security appliances as it concentrates on "new business directions".
Gartner's advice comes after Symantec told some customers on 23 June that it is winding down development of the Symantec Gateway Security (SGS) and Symantec Network Security (SNS) products.
"Avoid investing in SGS and SNS products. Move to other solutions at the next refresh point," a Gartner advisory written by analysts Greg Young and John Pescatore warned.
"Symantec is terminating its investments in the SGS multifunction appliance and SNS intrusion prevention system products. Symantec also recently ended support for the Symantec Enterprise Firewall product."
However, the Gartner report goes on to note that Symantec will retain the Network Access Control Enforcer and Symantec Mail Security products, as they are key to supporting the endpoint security products.
"Gartner analysis for Symantec network security offerings has consistently shown that Symantec has not had network security as a core focus, and that Symantec's offerings in this market have been 'niche' products," the analyst firm stated.
Gartner issued a 'caution' rating for Symantec's network security products, and said that the vendor's managed network security services offerings would be stronger if it did not have a channel conflict in selling firewall and intrusion prevention products.
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